He's always on. Yeah, now he's working. Yeah, he's always on. OK, now Professor Zheboydev from Harvard University will start his lecture series on stringy aspects of gravitational scattering. It's a great pleasure to be here. It's my third time in Trieste. The first time I came as a student for this, exactly this school. But the only thing I remember is a name in the face of my roommates from the school. So everything else I forgot. So my lecturers have two parts, and they're quite separated. So I will be talking about gravitational scattering and several aspects of it. And so the first part will deal with IR. Yes, and please ask me, stop me. Because I planned a lot of material, but we better not go there if it's completely un-understandable. The first part is IR, and by IR we mean low energies. And say, late time, large times. And the second part deals with UV, so to say. So it's high energies. And they're quite disconnected, as you can imagine, even though maybe they are, in reality, less disconnected than they seem. So today I will obviously start with the first part. So let me just erase that. And the useful, before I start, maybe just may write a useful reference to this part because it's a course taught by Andy Streminger recently. And the videos are recorded, so you can watch if there are 10 or 22-hour lectures. If you are interested, just look. OK, in the low energies, we, of course, expect gravitational theories, even if we think of gravitational theory as being some effective theory with high derivative corrections. At large distances and low energies, it reduces to Einstein theory. And usually one way to introduce this topic is to draw, or for some reason it is drawn as a triangle. So let me erase it, which represents the plan of the lecture. So what is this triangle? So triangle, let me draw it like that. So each of the vertex corresponds to set of ideas. And actually, each of these ideas is very old. So I'll try to write a little bit larger. So one angle is a sovereigns. That can be memory effect, memories, and third in asymptotic symmetries. These are three recurring topics. So if you consider scattering in flat space, that's what I will be mostly interested in. These are three things which I usually discuss, though, in different subjects and different areas of physics. So soft theorems, they deal. And here, the subject is very old. So the reference would be 64th paper by Weinberg. The soft theorem deals with low energy limit of scattering amplitudes. So if you have some scattering process and you take one of the particles, momentum energy of, let me write it, energy of the particle goes to 0, this describes the soft limit of the amplitude. And so Weinberg found that this limit's universal, and that's known as a soft theorem. Then the second corner is, say, asymptotic symmetries. And in the case of flat space, again, it's a very old subject. It comes from 1962 in the works of Bondi, Wunderburg, Metzner, and Sacks. And as we will discuss also in details, asymptotic symmetries are the symmetries which will be relevant to consider for scattering problem. But so the more formal definition you can write is that asymptotic symmetry group will be set off in gravity allowed, and we will discuss what it means, allowed defiamorphisms over trivial defiamorphisms. And you should think about it as a large gauge transformation. That's how they are called, also, usually in the literature. And the third corner is, say, memory effect. Here the relevant paper will be from 1974 by, at least in the gravity context, by Zildović and Polnarev. And this describes a residual deformation of a gravitational detector, actually. As usual, I will also discuss in detail residual deformation of a gravitational detector. So now these three subjects, actually, they were very old and they were pretty separated. So theorems, mostly a particle physicist, are aware of this, but it's sort of less known in the other branches. And asymptotic symmetry is a subject and the questions which people who are doing mathematical relativity are doing. And memory effects, people who are doing astronomy and astrophysics and study gravitational waves, they would know about this one. But let me write it as true. But until very recently, these very old subjects, which are 50 years old, were developing sort of separately. And the recent development was that they actually all the same thing in disguise. And the driving force, I would say, of these recent developments were this rich interplay that if you have astrophysicists, you think about detecting gravity waves and it gives you one insight. If you're a particle physicist, you have a completely different picture. If you're a mathematical relativist, you have a third one. And the power of this recent development was this interplay which was constantly driving. You know something on one side, you translate what it means on the other side. And in this way, many things, new things in each angle were discovered. But why would you say, you can ask why? So why would we study this old material? It's already 50 years old. And how did people come about these things? And my picture is that there are two major steps. Well, of course the big question, if you want a big question in this field, is always, let's say, flat space holography. We would like to understand, we would like to have something like ADS-CFT, where we have a non-perturbative formulation of observables in asymptotically flat spacetimes, what is the S-metrics. But at the moment, it says that the project is very far from that, and it was the stage of, let's understand the basics of this problem. And the recent excitement come from first, there was a paper on 2,000 Nain by Barnish and Thoasa who discovered sort of Virasora symmetry in the sky. Virasora, let me call it in the sky. I don't know if it means much, but basically they made this analysis of asymptotic symmetries. Olden, they found that similar in the stories from the 70s, which we just mentioned in the previous lecture, that you can extend the group of asymptotic symmetries, extend the group of global conformal transformation in the sphere to the local ones. And then the question was, they call it super rotations. I'll talk about it in details. And so it was very suggestive. What does it mean? Do we have a two-dimensional CFT? And people, my impression, got a little bit excited. And we're trying to understand what it means. And then there really is a flood. It opened in 2013. In the paper by Straminger, who sort of was able to understand at least two points of the corner. And then if I told you that all the things are the same, so you should draw the connection between them. So he was able to understand, to know enough about this mathematical relativity and particle physics at the same time, to understand what is a relation. And he explained that these two things are the same. And if you wish, this is the word. The soft theorem is the word identity of this, of this asymptotic symmetry. Then it was understood that if you think of this kind of residual deformations, which people discuss in astrophysics, they also naturally appear in this asymptotic symmetries as well. Sometimes it's called vacuum transitions, even though it probably causes more confusion than it helps. But let me just follow the literature so people understand the connection between asymptotic symmetries and memories. And memory, as I told you, it's a residual deformation of the detector to the response of detector at large times. And soft theorems, it's low energy. It's large time. And as you can imagine, that low energy and large times are related by Fourier transform. So these two things were kind of Fourier for each other. Not exactly, but. Sorry, yes. So yes, I have to explain residual. Let me explain it here. So if you have a gravitational detector, it's just say two particles moving on the geodesics. And then when the gravitational wave comes, they start oscillate. So the distance between them changes. And then the gravitational wave is gone. And there can be a residual effect that the distance between them is different from the original one. So residual is, in a sense, when we have some gravitational wave. And then the radiation comes, and the radiation is gone. And we again sort of end the vacuum. And this is exactly. So in this wording, this vacuum doesn't refer to a vacuum of quantum field theory, because it's statement that the radiation modes are not excited. And so the transition between one state without radiation to another state, well, people who study gravity waves are knew that there are sources of gravity waves. Well, actually, generic sources, for example, the one by LIGO, would lead to such an effect that there is a deformation, residual deformation, from the original state of an antenna to the different one. In this case, LIGO is sensitive at around 100 hertz. But this is a very low energy effect. So that's why it's with Earth-based interferometry. You cannot quite measure that. So now, basically, after this paper came out, since the end of 2013, there are around 200 papers on the subject. And if you have all these papers, you can sort of, I wanted to do this review, you can sort them by first choosing, so in which, say, which corner are we in? And write a paper on either some theorem or asymptotic symmetry on the memory. Then you can choose which theory you would like to consider, because even though I'm talking about gravity, just for no fundamental reason, you can talk about gravity. You can talk about QD, which is an even older subject. You can talk about supersymmetry. So you can choose your theory. So after you choose your corner and your theory, you can choose, so if we have a small parameter or a large parameter, we can expand in this parameter. And so there is what is called leading and sub-leading and sub-sub-sub-leading, et cetera. So theorems and the same translates to all other corners. You found the soft theorem. You question what is the asymptotic symmetry that corresponds to it. You found an asymptotic symmetry. What is the soft theorem? What are the memories? So you can travel around. Well, and of course, say, the number of dimensions also say, you can choose the number of dimensions. In some corners, you feel that number of dimensions is completely irrelevant. For example, if you're a particle physicist, you know that there are soft theorems in any number of dimensions. But if you're a mathematical relativist, you will find it very confusing, because say, people thought that there is no BMS symmetry in D larger than 4, et cetera, et cetera. So it's basically consort all the papers written on the subject in this way. And so this is a picture that's supposed to cover this, broadly this field. And I will focus on gravity in 4D in my lectures and try to explain the story in more details there. But please ask me questions now. So let's say we can take D equals 7, we take a gravity, and then you can ask, OK, so what can we say about gravitational scattering in seven dimensions? You can ask, you can study scattering amplitude. So you can study the asymptotic structure of field at null infinity. And then, depending on D, it happens that these questions, they depend on D and they depend on the theory. But in principle, and then you proceed to which order, because the leading order, everything is known, the subleading order. And of course, also, there is an E, which is sort of important E, which I forgot, which is classical versus quantum. You can start studying loop corrections and what happens, how to think about that. One thing also is I want to say from the beginning that I don't want to present the subject as something which is already written in stone, that everything is clear. I think that many aspects are pretty confusing. And probably in a few years, it will be a better way to think about it. So I chose my way through and tried to explain the ideas. But probably, maybe there is a better way, or it's developing quite rapidly. So any questions with this picture in these corners? OK, so now if you have this picture, you are already pretty far. Because we will not just discuss what exactly is the asymptotic symmetry, what is the memory, et cetera. And I would start with gravity in four dimensions. I would follow several steps. And these steps will be of increasing complexity, because so that we can slowly understand what's going on. Can I read here, or is it fine? So let me discuss gravity waves in flat space. OK, so let me remind you how the Lagrangian finds the theory look. We have curvature plus potentially corrections, matter and some high derivative corrections, which I will not be care about, because they're all irrelevant. In particular, as I will discuss a little bit, you can consider theories which are gravity. When I mean gravity, you can also add high derivative corrections, et cetera. But the nice thing about this IR part that is pretty universal and things which I will be talking about, they're pretty insensitive. You can add any high derivative corrections you like. It doesn't change the story. The questions of motions, of course, take the well-known form. T minus stands for the stress tensor. And now to discuss this effect, let's consider a very simple example. Because we consider a flat space plus some small perturbation. And well, there is some reference frame where it's small, so it's enough. And now we can, yes, also the I will be working in this lecture in a signature minus plus plus. OK, so if we consider this kind of perturbation, because as you know, due to different variants, we have a gauge symmetry. And the field equations would be there is a redundancy in the description of the spacetime of the type. So as a standard step, we can fix the gauge, which has many names. Lorentz, the Donder, Harmonic, I believe they're all the same. So let me fix the gauge. And then there is a residual, so that's a gauge condition. There is a residual symmetry, which, again, you can shift. You can make some differ morphisms with vector field. Laplacian of it is 0 and eliminate formal components. And in this way, we can end up describing what is called transfer stressless gauge, where h0 mu 7b0, trace will be 0. So it's very simple, and dj, dj will be 0. And the equations for, if we plug to the Einstein equations in the vacuum, we will find simply that box, htt, hij is equal to 0. So if we start in four dimensions, we have 10 components. This eliminates four. This eliminates four more. So this indices, i and j, they're transfers. So if you choose the direction of propagation of the wave, we have two components. And this corresponds to the fact that graviton has helicity 2. We have two components of the gravity waves. Now, that's you all know, probably. Now, how do we measure what is a gravitational wave detector? Gravity wave detector would be simply, as I mentioned there. We have a pair of particles. Say, each of them follows a geodesic. So if this is a massive particle, we characterize it by four velocity. Formical minus 1. And the geodesic equation is 4d tau, 0. So I hope this is also familiar. Now, when we study this memory thing, or just in general, we're talking about response. We're talking about LIGO. That's what we have. We have just particles that follow geodesics, which are given by these equations, where this capital gamma Christoffel symbols for the metric. Now, questions? That's right. Exactly. So in flat space, this gamma is a 0. Particles, I just say, stay at rest. And then when the gravitational wave comes, we will now discuss the distant changes. That's how we know that there is a gravity wave. Also, if we have some spacetime and this notion of distance, this is the notion of a distance between detector or synchronization of the clocks is coordinate independent because you can sit here and they can exchange signals and say each other, I observe this time, and I'm here. And then by measuring time, it takes light. They can measure the distance. They communicate via exchanges, but it's not very important now. OK, so now let's consider the solution to the correction to the metric due to the presence of the gravitational wave. That's very simple. So I chose this coordinates as the following.  And because the gravity wave is just a function of retarded time, this is a solution or finds any questions to the first order. And then the wave travels in x3 directions. And all as an exercise, you can check that if a particle stays at the fixed position, say, z bar 0, this is, if you take this metric, you compute the Christoffel symbols, you find the geodesic motion in the spacetime, you can check z and z bar as a geodesic equation. Now imagine that we start with two particles, which separated by some distance in the z plane by some distance delta z. So there is a distance delta z and delta z and delta z bar. Now as I just told you, that this separation in coordinates z, it's solved geodesic equation for any time. But as time progresses, the metric changes. And in particular, we can consider this function h, something which maybe starts from 0, nothing comes. Then there is some gravity wave. And then there is a ring down, and then there is some residual transformation. And consider such. And this is time. Now as h changes, the distance between two particle changes. And this can be seen that by just evaluating, if you take two points at the same time and the same position x3, and evaluate a user metric to compute the distance, we find that the L of u is L0 z square plus this effect of the wave delta z square plus h z bar z bar delta z bar square. Now this is called gravitational strain. And so for the, again, just as a warm up for the LIGO event, this is 10 to the minus 21, the maximal peak. So it's pretty small usually. That's why you have to have a very sensitive detector. But now notice that if we say, this function of h of u can be arbitrary here. In particular, we can choose the original and the final value to be different. In this way, the gravitational wave comes. The distance oscillates. And then after the gravitational wave passed, we had some residual deformation. This residual deformation of a gravitational detector is called memory. So that's a simple. Yeah, it's a distance. It's a distance between two detectors. So we have a space time with a fixed metric. And we have two positions of the detector. So for example, I send moreover, as I will discuss, it's a flat space. So we're just in Minkowski space. We use perturbed metric. We use perturbed metric, yes. But let me now ask your questions in a slightly. Actually, how long can I go here? Is it better stop or is it fine? OK, you don't see. OK. So what is the final space time? Well, the final space time is, let me go here. The final space time is simply that. It's ds squared minus du. Yes, and I refer to Wikipedia for Christoffel symbols and Riemann, so I don't write them. Please check Wikipedia or any other book you like. So the final space time is this, where h final is this final value of the metric. And it's a constant value. It's just a number. Notice that we are working in a linear theory. You can check as an exercise against that this is a flat space. This is just flat space. And you can make it if you have morphisms, which looks like that, which will bring the metric into the usual flat space form. So we can either use, and basically in this simple example, we have the original space and we have a final space, which are both flat space times. But they differ by this defer morphism. And you might think, and in many usual texts and treatments of GRs, that two spaces which differ by defer morphisms, they should be physically equivalent. And somehow the whole driving subject or recurring topic in this story is that sometimes it's meaningful to talk about this large defer morphism, such as a physical. And you should be careful when you talk, even though there is just a flat space, and the two flat spaces which differ by defer morphisms, they can be meaningful. For example, here when we do this, if we follow the detector and we do this transformation on the metric, it will become just the original metric of Minkowski space. But as soon as we are acting on this with this transformation, the detectors, on the positions of the detectors, they will be not invariant. And in this way, we can either detect this change in the length by looking at the metric or equivalently, we can make it defer morphism. The endometric is Minkowski, but this residual memory is encoded in the positions of the detectors. So this large defer morphism in the context of the whole Minkowski space will, well, let me just mention them yet. They will be analogs of, say, something which is called super translations. But here now we are not discussing. We are doing a very simple, very mundane local analysis. Nevertheless, we have sort of main ingredients with slowly emerging. Now, let's ask what is the relation? Yeah, why also one thing which, so you might think that electromagnetism is simpler than gravity. And this is one of the instances when that's actually not. Because, as you know, in quantum electrodynamics, gauge transformation, when it act as a detector, in which in this case would be a particle, say, it adds to the phase. And the classical phases of particles are not observable. And to observe them, we should do some kind of Aron of Bohm effect. So in QED, the analog of memory is Aron of Bohm effect. That's a dual description QED. So H is small. H is small. I worked for first order and H is a small parameter. And this is Minkowski space. Well, here, yes. But if H is. Do you expand? Yeah, yeah, I am. Yeah, I'm sorry. Here I was working to first order in H. Everything so far. We can do, at the end, I will do all the statements precise and full in full nonlinearity. But here, for simplicity, I just work the first order in H. Let me not call it largely thermomorphism here. Sorry, I'm sorry. Let me. It's confusing. I don't want to call it largely thermomorphism. Yeah. Right, at the moment, this is an assumption. But we will see that that's what happens. I will show that for the sources, which corresponds to the problem of scattering, this is what happens. So, and moreover, we will see that, well, that's more or less in gravity that is what happens. That's the only thing that could happen in the difference. For example, there are sources which go to zero at the end. So at the moment, it was just an assumption. And now the simple comment, of course, that if you want to do a Fourier transformant, if you define the Fourier transform of this wave, then this residual deformation, this delta H, is encoded in the pole at low frequencies. It's, again, trivial statement. But it will be exactly what's happening again and again. So again, if you take a function of this type, you do a Fourier transform. You will see that this change is encoded in the pole of the function. And you see that in this way, we see that there is a soft theorem and the soft radiation is related to this large time effects. And when I will be talking about Minkowski space, of course, it's the full space. It's much complicated. But if we are observers who are sitting locally here on Earth and we have an antenna, that's what we see. Now let me move, start making things more confusing. And to make them more confusing, let me switch to a global picture of a spacetime and draw. So when talking about scattering problem in Minkowski space, it's useful too because Minkowski space is infinite. It's useful to put it in a finite region. And this is done by means of the so-called conformal compactifications. If we want to discuss a causal structure of spacetime, so we rescale the metric by conformal factor. And the known fact is that it doesn't change the causal structure. And by judiciously choosing conformal factor, we can make infinity a finite distance. So let me discuss Penrose's diagram of Minkowski space.  This is, let me maybe write some useful coordinates so that it is a metric of Minkowski space. So we have time, radial direction, which goes from 0 to infinity, an angle on the sphere. And on this diagram, the time goes horizontally. This is the slices of a constant time. This is a t constant. This is a constant R. And the interesting part is the boundary of this region, which is infinitely far away on this diagram. And there are several things which people usually discuss. So they are called I plus. I plus is a future time like infinity. That's where massive particle end. Then there is something which is capital calligraphic I plus, which is called Scri plus. Scri plus. It's an null infinity. That's where light ends. So the great thing about Penrose diagrams is that light propagates at 45 degrees. Then there is I naught, which is called spatial infinity. And then there is I minus, which is called Scri minus. It's a past null infinity. And then there is I minus. One thing which you might maybe remember is that, and will be important for us, that even though on this diagram, all these three regions, yes, sorry, and at every point here, this is a two-dimensional diagram. We have four-dimensional space. So there is a two-sphere hovering everywhere, which denotes the angle on the sphere. So one important fact about this diagram is that even though this null infinity is and spatial infinity merge at the point, they actually, this configuration is singular. And when we will be approaching, if you imagine a big barrel or big cylinder in spacetime and you start making it large, and then trying to discuss how we approach I plus and I minus, I don't know, for example, if you have some observer that send light here or here, we will find that this null infinities will be actually infinitely far, even though when we will be, even though they merge here at the point, in a sense, in certain situations, it's important to remember maybe to think about approaching this point as a limit from an observer that fix time who are going at large distances and send lights to the future and to the past. And then we will see that this data, even though on this diagram it can be at the point, it can be actually pretty far. Sorry, let me maybe not, the moment it's not saying more about that. And now the scattering problem corresponds to the something of this type. We have a, what is the scattering problem? Well, we specify the data. Something comes in, some particles. And then comes out, given an initial data, what are the waves coming from minus infinity? The problem is to find the result, square plus. And now to discuss this global structure, yes, and for example, let me write what, yeah, I will be scattering just some massless particles. I will be thinking, even though we can scatter massive particles coming from here, anything, we can scatter whatever we like, but simplicity, we can scatter gravitons, photons or any massless particle. But now, so I would like to repeat the previous exercise for this kind. Oh, this is not, here it's not 45 because here it's not massless. It could be a rocket or it can move on the sphere. So, so it's, maybe it's a, we can draw a better picture. Imagine, let me consider, that's what I want to consider now. So, we have a point, we have a light cone. So, for this kind of picture, we will just have one line. So, I wanted to resolve them sort of on the sphere. And now, we can imagine particles coming along null rays and going in some direction. So, they collide at the point and then proceed to null infinity. This to the leading order, let me describe this process as just a given stress tensor in Einstein equations. And the stress tensor is, say we have some of our particles integral over the proper times, their momenta, is there for velocity. And then we have a delta function that's the position of the particle, which is. So, this is a stress tensor for a set of incoming particles for t equal less than zero. So, it is localized at the position of the particle, which is given by unit times tau. It moves in time. And it's stress tensor is related to its momentum. For velocity. And then as they collide, we have the same kind of sum, but we have a set of final momenta with some other choice of positive times. Now, we're asking the following question. What happens if we, before we observe the local gravity waves, but what happens if we have this gravity wave coming from the event of this type, where particles coming from infinity collide and then they go to infinity again? Well, to do that, to find what h is, in this case, we simply need to solve, we simply need to solve the, well, equations of motion for the h. And of this type, indices. And then, so we get the, we need to, if we have a question of the sort, the h is equal to the integral over space time.  That's what we need to do. So that's how we find the field from a given source. Now, let me, what's a little bit in more details? What's going on? This integral is, of course, very, it's very easy to do. Something subtle that might happen unexpected. So let me focus my attention on the detector, which sits. First of all, so this is the usual coordinates.  Now, if we take the limit u fixed and r to infinity, that's a limit where we are approaching this scri plus. So that's where the light goes. Well, I would like to compute now the metric in this equation. h is a function of, h is a function of u and r, some angle on the sphere. So to do it, recall that the retarded, the retarded propagator is this. It's a delta function localized along the light cone. So if you have some source, if you have a source, you can draw a light cone and from the source, and that's where the green function is localized. So it's very simple to do this integral. It just gives us a delta function. So what we need is actually to compute something like this. We need to compute the integral d tau and then we have a delta function of x minus u mu tau square. This is just this delta function. And the four integral here is gone because of this delta function. Okay, it's very simple. This integral is completely localized. But what's interesting is that, let me just write some in details. So we have x square minus tau to x u for momentum minus tau square velocity. And now in this coordinates, if you take this limit, to take the limit of large r and fixed u, we find that this say x u becomes a product of r times n u. So it's linear in r. And here n is related to the, it's a four vector related to the direction of observation. If we have a detector at the position given by some three vector, unit three vector, then x u goes to r, this n four vector n dot u. And then an x square goes in the large r limit. It's also linear in r due to this piece. This term r times u. In this way, you can find the tau. You can let me leave it as exercise. You find the tau, you plug, you solve that this equation should be equal to zero. And then you compute this integral for the sum. And of course I almost did the computation for you, but the result is that, the result is very simple that, so h, let me actually write immediately as, so h will be equal to say theta.  And this thing is, so there is a jump. It starts with a constant value and it ends in the other value. So there is a change as we discussed before. And this change is just what is known as a soft factor. Take the difference between the two. Now several comments in order. First, you see, yeah, that's an important thing. Thank you. That's r. So the leading, we take an r to be large and the metric decays with r. So decays linearly with r, with this change. Moreover, it's, well, now let me do the following remarks. So first, this thing is known as a soft factor and it appears also, for example, in the, if you take maybe, let me just postulate it. Now, I haven't derived it, but you will get the same expression if you compute. You take this pre-factor. You take a limit, soft limit of the amplitude, energy of one of the graviton goes to zero and it's related again to this exercise we did where we saw that it's, this residue is related to the pole in the Fourier transform and here now we are saying that for this kind of scattering with the source, the source of the pole is controlled by a soft limit of the amplitude. Now, another important point in this, I will use my, I will end on it. It's a very, it's very crucial actually. Maybe I would even say that in the original paper by Strominger, that was a crucial, crucial insight, which is not completely, well, actually, yeah. Yeah, so here I, what is A, right? Oh, great. So let me explain what is meant here. So this is, this model that we consider with the sources, of course it's a model of a scattering amplitude. We consider scattering amplitude with this momenta, pi one, p one, p i, this is final one. Now, this is what is meant by a n. This is a scattering amplitude with the same momenta as we used for the source. Now, omega is a statement that we consider amplitude where we attach one more particle, which is a graviton in this direction of sight with this momenta. So it's a graviton attached in the direction where our detector is inserted. And now this is an identity, this is a statement that this factor that we found here, which come from the sources. It's actually completely universal and this change, it is totally insensitive. So here's the sources we're interacting at the point. But the result for the change, which was in this, we obtained in the simple model, it's completely universal and is insensitive to the, the details of the process. And actually this would be completely general. That's the meaning of the formula. Yeah, I wanted to explain this crucial insight, but maybe I'm out of time. I better start next time. Thank you.


Good morning. My name is Julie Larry, and I'm a trustee at Greater Portland Landmarks and a member of its Public Issues Committee. And I want to thank you all for joining us this morning. Greater Portland Landmarks Places in Peril program calls attention to significant historic buildings, neighborhoods, landscapes, and objects that characterize the Greater Portland area. These are resources that may be lost, some slowly, others a little bit more quickly, from a variety of types of threats. While Places in Peril is the only program of its kind in the state of Maine that focuses on a specific region, endangered property lists are used throughout the country to highlight and raise community awareness of the importance of historic resources to help gather people together to raise the resources for the protection, preservation, and adaptive reuse of historic properties so that they can continue to be a vital part of their community's architectural character. Earlier this year, Greater Portland Landmarks solicited nominations from the community, and we received 26 submissions. We have chosen seven resources based on their historic significance, the severity of the threat facing them, and the benefit that could come from a Places in Peril listing. These properties selected this year are located in Portland and South Portland. And now I'd like to introduce Hillary Bassett, Executive Director of Greater Portland Landmarks, who will give a little bit more explanation about the different properties selected for this year's list. Thank you, Julie, and welcome, everybody. My name is Hillary Bassett. I'm Executive Director of Greater Portland Landmarks, and I'm very pleased to announce our second annual Places in Peril list this year. We started last year, and this year we're continuing the program, and really there are several major reasons for it. Some people think that preservation is already complete in this area, and it's absolutely not the case. We like to call attention to properties that still need preservation, and especially those that are what I call a tipping point, a point where they could actually fall into ruin or even be destroyed or lost forever. So this year, we also are doing this program for three major reasons. The first is to build awareness. Second, to advocate for preservation, and the third is to convene people and provide access to resources, and to provide advice on how these properties could be preserved. I'm gonna start with our first property, which is Fort Gorges. Fort Gorges is a very important fort in the Portland area. It's a major landmark in Casco Bay. It was built in 1858 to 64, and it was state of the art construction in the Civil War era. It's actually modeled on Fort Sumter from Charleston, South Carolina. Unfortunately, once it was completed, it actually became obsolete because the technology of warfare had changed during that period, and so a masonry building couldn't hold up to the kind of artillery that was present by the end of the Civil War. Notwithstanding, it is a major feat of engineering, building a fort in the middle of Portland Harbor. It has stood firm in that location for many years. The federal government actually transferred that to the city of Portland in 1960, and the city has owned it since then, and it is an excellent example of the engineering and technology of the mid-19th century military construction. Now, what's the threat? The threat really is lack of maintenance and deterioration of the masonry. It is a very solidly built structure, but the mortar is being lost between the joints. It has had no maintenance, and it is in danger of ultimately falling into ruin. So what are the opportunities with this site? Well, first of all, it would be an excellent opportunity for the city to develop a master plan for the site. How could it be preserved, and how could it be more widely used? There's an opportunity to provide greater access, and many people currently access it by kayak or other means so that people can see what is out there. There is also an opportunity to recognize the significance of the site for the greater Portland area, and also there have been several groups of citizens who have expressed interest in preserving the fort. So there's an opportunity to gather and convene those people to ultimately preserve fort gorges for the future. I'm gonna show you a few additional images of it, if you can see them. That's looking into the parade ground. There's a parade ground right in the middle of the fort, so it's a big open field in there. Here's some of the masonry and that dripping white stuff at the arches. That is the mortar that's being leached out and forming those little driplets. And there's another example of the mortar and the stone construction. And here's the parade ground in the middle. Again, from the exterior, you don't see that, but there's this big open space in the middle of the fort. The next site is the Western Cemetery. And Western Cemetery is Portland's second oldest cemetery. It's significant, especially because it's architecturally, because it's in the transition period between the old burial ground, community burial ground, which is just a group of gravesites to an actually designed more rural-type cemetery. So the style of cemeteries changed to be a more rural and with pathways, a more designed kind of a space. That cemetery was Portland's main cemetery from 1829 until 1852 when Evergreen Cemetery opened. And Evergreen was even carrying the idea of the Garden Cemetery even further and many families moved their tombs to Evergreen. Now there are still 6,600 burials in Western Cemetery. So it's a very important site. There are many important families tied to it. It is tied to the Irish history where many Irish citizens are buried there. So it has a long tradition with Portland history. Now in 2001, the city of Portland commissioned a master plan for the cemetery and they've been slowly working toward it. There's also a citizen's group called Stewards of the Western Cemetery that's been affiliated with the cemetery and they've been able to raise some private funds to replace the fence. There's a fence along Vaughan Street to repair the ceremonial gate to the cemetery and that's the one you're seeing here. They've been able to raise some funds for that site but there's still a huge need for fundraising. Many of the recommendations of the plan have not been implemented. There's a full budget and prioritization in the plan. The Stewards have done a great job but they need help. So the threat here is lack of maintenance, lack of attention, lack of funding and neglect. So what is the opportunity? Really it's to increase awareness of this cemetery. Again, outside the Western Promenade neighborhood many people don't know it exists. There's an opportunity to advocate for the city to provide the funding to implement the master plan from 2001 and also an opportunity to work with the Stewards of the Western Cemetery, the community group to help them build awareness, education and also to raise funds for the preservation of the cemetery. And I'll show you another couple of shots. These are the tombs in the back of the cemetery and there's some well-known but not so well-known names today. A long fellow is one of them you'd recognize. And then here's the actual cemetery itself. It retains much of the original form but it needs more maintenance and attention. Next site is the Ingram Carriage Barn. This is located right around the corner at the corner of Pleasant and High Street. It is circa 1800. So it is built right at the time of the McClellan House across the street. So it's built in the period when this neighborhood was the neighborhood where the wealthy families of Portland lived. It was built by Elihu Deering and the Deering name is a commonly heard name in Portland. And it is one of the very few surviving carriage houses from the federal period era. So it's a form that is very unique and one of the few remaining. Now the site, the building itself is in the, the main building is in the historic district, the Portland's historic district and the carriage barn is listed as a significant element of that structure. Now the site has evolved, the building had an L on it that connected the carriage barn that's been demolished. The building was a private residence when it started and now has been, is used as an apartment structure. It's currently owned by Goodwill Industries as the owner. So the threat here is the neglect, lack of maintenance and lack of the use for the property. And what is the opportunity? This property is located in a great area. It's close to the arts district. It's close to downtown. It's of a relatively modest scale. So it has potential to be an art studio. It could be residents, could be small office. So there's a lot of potential that could be realized by rehabilitating this building. So we'd like to encourage the owners to consider that and also to, because of its location and being in a national register area, it could potentially be qualified for historic preservation tax credits. So the rehabilitation could be promoted by access to tax credits. And then of course near term, just to keep this building stabilized until a plan can be arrived at to preserve it for the future. And I'll show you the rear view. This is the same site looked at from the rear. Now our next site is Lincoln Park. And Lincoln Park is the city's oldest public park. It was built in an era when the city of Portland was recovering from the great fire of 1866. So the city has this great fire 1866. Part of the reason for Lincoln Park is not just to have a park but it's also to have a fire break right in the middle of the city. And much of the original features of Lincoln Park are still there. So there's the fountain, the fence, the beautiful fence posts are still there. There's also been a major change in the park however. Back in 1970 when Franklin Arterial was being built, a quarter acre of the park was cut off the park. So if you've wondered why the shape is a little bit unusual, it's because it was cut off in the 70s. So the threat with that park, and I also should mention that recently Lincoln Park was in the news because it was a site of the Occupy movement. And so there was an encampment there in 2012. And then after the encampment, there was a citizens group formed called Friends of Lincoln Park. And this group is actually working very hard to pull together resources from the city and try to build awareness of the park so that there can be improvements in the park. So what is the threat? Obviously it's been, the park has been ignored for a very long period of time. There's been a lack of funding. And also this is very current because Franklin Arterial or the Franklin Street study is happening right now. And in that process there's an opportunity to restore that quarter acre that was cut off Lincoln Park. So this is a chance to get the park not only to get attention and rehabilitate the park but also to get it back to its original configuration. So that is a very timely and current reason for this property to come to public attention. The opportunities, obviously, let's get the park back to its original configuration to work with the Friends group, Friends of Lincoln Park to advocate with the city to get the funding to restore the fence, to get the fountain back working, to restore the paths. The materials are all there. All the original materials and features are still there. It's a matter of getting it restored. And here's another couple of views of Lincoln Park. Just to show you that the forms are there but the paths are deteriorated, the grounds aren't maintained. So now, Lincoln Park, we segue into the Neil Dow House. And this is a fascinating building. It's on Congress Street. It is affiliated with Neil Dow who was a very major political figure in the 19th century. He was a Civil War general. He was also the head of the Portland Temperance Movement. He was known as the Napoleon of Temperance. And in the 19th century, Neil Dow actually started a big effort to prohibit the use of alcohol. And he actually drafted what they called the Maine Law which was the first anti-alcohol or prohibition statute in the country. And that was used as the model for the national statute that was approved in 1920, the prohibition statute in 1920. Neil Dow was also, his family was also affiliated with the abolition movement. So that house was a site on the Underground Railroad. There are two, he documents at least two instances where the family housed African-Americans who were fleeing slavery in the house. So here's a property that has a lot of great ties to history. So it's got a lot of ties to history. So it's a tie. And also in the 1930s, Neil Dow's son bequeathed the house to the Women's Christian Temperance Union of Maine. So the Women's Christian Temperance Union started in the late 19th century. They had decided that alcohol was the root of many social problems. And so they had a major role in promoting temperance. And then ultimately, many of the women involved with that group became involved with women getting the vote. So this property ties to abolition, it ties to women's history, it ties to temperance and the Civil War. So it's all wrapped up in this site. So what's the threat here? Nobody knows about this place. It's right in the middle of Portland on our main street and nobody knows about it. The Women's Christian Temperance Union Maine chapter owns the building. They've done a good job maintaining the structure. But the building moving forward, these historic house museums have a very hard time raising money through adjusted missions. So long term, there will be financial needs, short term, more people need to know about this very important site. So the opportunity here is really for greater awareness of the importance of this building to American history. It is also an opportunity, there's an opportunity to set up a separate non-profit just to preserve the house because the goals of the Women's Christian Temperance Union are a little bit different than just maintaining a house. They have a social services mission. So there's a lot of opportunity here, I think, to build the educational role and build the awareness of the community and then to create partnerships with local groups to help preserve the building. And I'm just gonna show you a little, this is a little bit dark, but you can see the interior of the building. There's a wonderful library, Neil Dow's library and many of his original artifacts are in the house. So that is an important location here. Now, it wouldn't be landmarks if there wasn't a statement about Union Station. As you know, was the demolition of Union Station in 1961 was part of the reason that landmarks formed back in the 60s during that era when a lot of older buildings were being destroyed. And the Union Station clock still survives. This is another unsung landmark of Portland. It is housed in a small brick building in Congress Square. It is still working. The clock was built in the 1880s and installed at the top of the tower of the Union Station. And then in the mid 1980s, the main central railroad actually donated the clock and all its works to the city of Portland and it was installed in Congress Square Plaza. So that's the story for landmarks. This is a very iconic symbol, one of the last remaining pieces of Union Station which was such an important site to the city of Portland. So what's the threat here is lack of awareness number one and secondly, currently the Congress Square Plaza is under discussion for in the city. The city has, Council has approved an agreement to sell part of the Plaza. That site includes the part that has the clock installed on it and yet there is no plan for what will happen to the clock. There is some funding that the developer has agreed to to pack it up and move it away but there's no plan as to where it will go. And there are a number of concerned citizens and neighborhood groups that are interested in a future plan for the clock. So again, opportunity here is to recognize the importance of the clock that it's even there and then also to find a location that will honor the history of Union Station and the clock. And then our last of the seven is a little bit different kind of a category. This is the historic properties of South Portland and as many of you know, there's a wonderful history in South Portland. It's a community with many interesting, there's seven historic neighborhoods in the city. It's a town that was actually founded in the 1600s and incorporated as a separate town in the 1890s. So there's a long history of development in South Portland and there are very few buildings that are even listed in the National Register. There are only three buildings listed in the register. Two of them are lighthouses. So there's a lot of opportunity for more recognition of buildings in the community. And there are wonderful neighborhoods and I'll just cite a few of them. Ferry Village is one which has got an incredible architectural history just reflected in the buildings from the very early 1800s through the shipbuilding era of the 19th century into the 20th century. There's Meeting House Hill, which has fabulous residential stock as well. The Willard Beach area, which is a very popular residential area now, but also once had a casino and once was a fishing area. So there's a lot of history in South Portland. So what's the threat here is nobody knows about it and it's not, there are no protections. There are no protections of historic resources in South Portland. So we feel that there's a tremendous opportunity to build public awareness of the buildings and neighborhoods there, to provide recognition, to do a survey, even the basics of figuring out what's there by very systematically going through the neighborhoods, identifying the major properties. There is an opportunity to, in the education side, the mayor of South Portland offers a course in the history of South Portland and Portland architecture. So just building awareness of what's in South Portland and then potentially getting more properties listed on the national register that those, especially if they're income producing can provide access to tax credits and just recognition of what's there because what's been proven time and again is historic preservation helps economic development and neighborhoods that have protection, those properties tend to be stable neighborhoods and increase in their property value. So we think there's a great opportunity there and I'd like to just show you a few properties, but there's many, many more different neighborhoods. This one, this house is in Ferry Village. Here's a church that was recently highlighted in near Broadway that's deteriorating. A school in the Thornton Heights area. A commercial building, a kind of what I would call bread and butter commercial building in the Pleasantdale area and then one of the homes in Meeting House Hill. So South Portland is just an incredibly historic area but no one knows about it and it's not protected. So we feel it's deserving of being on the list. So that's our list. I wanna show you the distribution of properties this year again. We're a little bit heavily focused on Portland with six sites, well actually five in Portland, one in Portland Harbor and then the community of South Portland and its historic resources as our seventh property. So thank you very much and now I'd like to ask Nate Stevens to say a few words. Good morning. My name is Nate Stevens. I'm a trustee on great Portland landmarks and a commercial real estate broker with CBRID, the boldest company here in Portland, Maine. Congratulations to the committee on the 2013 Places of Apparel. I actually was just saying recently before this that I was at Fort Gorge just a couple of years ago and actually fell partially through one of the floors so I'm glad to see that's on the list. But being a commercial broker in Portland and in the business community, I see firsthand the importance of historic preservation in the business community here in Portland and other downtowns locally. And the importance of these properties and these landmarks and places like them in the marketing of Portland and our other downtowns to businesses outside our state to bring them here to Maine. I've spoken with CEOs and other business leaders here locally who have their businesses in Portland have located their businesses in Portland because it's an identifiable town. Without our historic buildings you could be any other town in the country. However, historic fabric defines our town. I work with companies small and large, local, national who wanna be in historic buildings. They have specific requests to be in historic spaces. They want the character. They want the exposed brick, exposed beams, the high ceilings, the woodwork, some of the grand lobbies that you see down in the old port, the conversation starters. I believe that it's spaces like this that help create creativity, conversation, movement within a space and tie the business and the employees to the local community and its history. You walk into a lot of the lobbies here in downtown Portland that was actually in a lobby in Westbrook of a local business where you see historic photos in the reception areas of the buildings that they're in just plastered on the walls. And I think that's a clear indication of the pride and the local support within businesses of the historic preservation and the buildings that they house their businesses. And I think that interest within the business community has helped developers take advantage of historic tax credits as Hillary was mentioning earlier and redevelop buildings that couldn't be recreated otherwise. For example, recently, Pierce Atwood, which is in the Merrill's Wharf building down on the Port of Waterfront, and the Baxter Library on Conger Street, which houses the Via Group. I think two very important buildings that could have easily been on a places in peril just a few years ago if they hadn't been redeveloped. So I think it's important to note, while it is important to obviously know the historic preservation with the heritage tourism here in Portland and bringing people to live to our towns and our communities, I think it's equally important to notice or to note the importance of historic preservation within the business community. So it's getting congratulations and thank you very much. Are you happy to take questions from anyone? Just in the second year, we've just done this. The seven that were identified last year, have you talked about whether or not you've seen any movement about happiness awareness here today? Yes, we have, we have a seven. Okay, yes, we thank you, David. Yes, we've seen some movement, not on all properties, but on several of the properties. One of the most important was the Abyssinian Meeting House got national recognition and that property was selected by the National Trust for Historic Preservation as one of their 11 most endangered and that is a nationally competitive program. So Maine, to have a property in Maine and in Portland listed is a very significant achievement. I think it's the first time that a property has been listed for Maine. So, and that's given them a huge boost in terms of the opportunity for national visibility and potential for fundraising to complete the project. A couple of other Eastern Cemetery listed last year, they have been successful in achieving some city funding for needed work there. So they've needed access to water for maintenance of the cemetery and there's the receiving tomb, which is the little house in the cemetery. They've received some allocations for funding to help repair that. Masonic Temple has actually begun work on a fund drive to help preserve the building. So they've been very, very, how can I call it, systematically going forward to help restore that building. I think listing the places in peril has provided them with more visibility as they go out and raise funds to help restore the building. So those are some examples of how the program has helped move these projects forwards. Why put all of South Portland on the list rather than maybe focus on a few properties in South Portland to give those properties special attention? Are you concerned that by generalizing, you're actually not doing what you're trying to do? I think that you could, I think we felt that there's so many historic resources there that are unrecognized that this would be a way to introduce the subject. Obviously, there are many individual properties which could be recognized. And what I found in just doing some of the, driving around the community was there are many wonderful, as you turn a corner where you have a wonderful surprise where there's an old school that's been converted or a church that's still remaining or something that really ties into the early history of the community that's unknown. So we felt also that the opportunity to do a survey of South Portland is so strong to see what's there that this would be a way to call attention to that need. Because obviously, the first step is really identifying what's there so people can know what's there and what to do. Questions? A lot of this is sort of driven by funding. And many of these properties have some city affiliation and municipalities are not known to be fleshed with money. And I wonder what responsibility is this, the city share to these properties and how much that can be shifted to other groups as a way of not putting the entire burden on the city. So the question is, many of these properties have an affiliation with a municipality or city. Those entities are strapped for resources. What other solutions for funding? And one of the things we've found really effective is the Friends Group that Friends Groups partner with municipalities and community organizations. A good example is the potential now with Lincoln Park with a new Friends Group. They're super motivated. They're out making connections with city leaders participating in the process. And that can be a very powerful tool. Can it also be counterproductive when those Friends Groups don't always have the same goals and ideals as the city's increasing the Congress for a positive? Sometime, what I would say to that is that typically like Friends of Lincoln Park, what works really ideally and best is to first create a master plan. And we saw that with Eastern Cemetery where the Friends Group partnered with the city to create a master plan. And then they're all working toward the same goal. So even if it's a small thing, like where do the plantings go? What are the priorities for preservation? Same thing with the Western Cemetery now with the Stewards Group that there's an opportunity there to put forward the plan that's already in place in 2001. So those are agreed upon goals. So yes, so depending on which groups you're partnering with there could be disagreements but we like to take the positive tack and that in many cases the citizen engagement really can be extremely positive in leveraging more resources.


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