Can LIGO ever be made in India?

Nobel Prize in Physics"Now we can hear the universe"

Ralf Krauter: Yes, but the alarm bells didn't ring in Louisiana, where it was just night, but in Hanover among researchers at the Max Planck Institute for Gravitational Physics. When the death scream of the black holes hit the earth, the German members of the LIGO cooperation were responsible for the data analysis of the detectors. Their boss has been Professor Karsten Danzmann, director at the Max Planck Institute for Gravitational Physics, for many years. I asked him earlier, what was it like on September 14, 2015, when the first gravitational wave hit you?

Karsten Danzmann: Yes, that was all completely unbelievable, there were actually two postdocs in our institute, the first people to ever hear black holes die. It was 11:50 a.m. on a beautiful Monday morning when Marco Drago was sitting in front of his computer and received an alert from the Online Search Pipeline, which had found something strange in the LIGO data, and looked at it and thought nothing more and suddenly saw something on his screen that looked like what we've been looking for for half a century. It looked exactly like the merging signal of two compact objects. Then he brought in his colleague Andi Lundgren - just have a look at that - and the reaction of the two was just like the reaction of all of us later: disbelief. We didn't believe it. If you look for something for so long and you suddenly find it, then you don't suddenly call out, Eureka, I found it, but then you are initially skeptical and say, well, we have to take a closer look at that. As a scientist you know that a lot can go wrong, it can rustle - you have to look very carefully at that. I would say it took me two or three weeks for the first time to allow myself to begin to believe that something really big had just happened. And it took months until we were finally convinced that what we had was pretty much real.

Herbs: But when you were convinced that this was real and not a pipe dream, did you already realize that it would be the material for a Nobel Prize?

Danzmann: Yes, that was always clear from the beginning.

Herbs: The Nobel Committee decided today to award the Nobel Prize for the first experimental detection of gravitational waves, half to Rai Weiss and a quarter each to Barry Barish and Kip Thorne. In your opinion, is this weighting of the awarding of the award okay, is it appropriate to the proportion of the individual researchers?

Danzmann: Oh, I don't think we should go too far. Yes, they meant well, it is also the case that Rai is certainly the great figure who shines above everything, but whether 25 percent or 33 percent, "personal merit" is not an exact science, it cannot be measured. There will certainly be a lot of discussion about whether it should have hit these three too. There is a lot of inner sense in what the committee did: Rai Weiss for the beginnings, Kip Thorne for the theory and Barry Barish for the entire team. It's difficult when so many people were involved in a great discovery. You have to represent them somehow, and I think that worked out quite well here.

"We are all represented by the character of Barry Barish"

Herbs: How painful is it for you that, in the end, the European contribution has been completely ignored, at least it was the people concerned? You and your people at the Max Planck Institute for Gravitational Physics also made important contributions to the whole undertaking.

Danzmann: Yes, I think we have to separate that from each other. We are all represented by the character of Barry Barish, and as far as the contributions are concerned, there will still be a lot of talk about who contributed what. Scientists don't do their work for the price, but from an inner drive, and we all know what we've contributed, and that's enough for us. This Nobel Prize is ours too.

"German researchers have played a pioneering role in the field of gravitational wave research for half a century"

Herbs: Nevertheless, there is such a small drop of wormwood, perhaps because many of the original concepts were also developed in German laboratories and because Germany itself was once well on the way to building such a large gravitational wave laser interferometer detector - there was a lot of concrete plans in the late 80s, early 90s. How did you ultimately fail?

Danzmann: Most people do not know that Germany and German researchers have played a pioneering role in the field of gravitational wave research for half a century. My predecessor in the Max Planck Society, Heinz Billing, was one of three people in the world who, half a century ago, tried experimentally together with Rai Weiss and Jo Weber to detect gravitational waves. That went on for a long time, and Germany was always at the forefront until the beginning of the mid-1990s when the BMFD turned off the tap and stopped promoting gravitational waves in Germany.

"The LIGO detectors could also have been in the L√ľneburg Heath"

Herbs: So the Federal Research Ministry ultimately made different strategic decisions.

Danzmann: Yes exactly. At that time the LIGO proposal was on the table, but also the GEO proposal, which we had written together with British researchers, and I would say they were in about the same state of maturity. Shortly afterwards, the Franco-Italian Virgo Proposal also came. While LIGO made good progress in the USA and was finally approved by Congress as a separate entry in the budget, the gravitational waves in Germany fell backwards - for various reasons. It has never been fully clarified why. Maybe it was just that in the aftermath of German reunification, people had no leisure to think about something strange like gravitational waves. There was an entire academy of science to be dealt with in the East, and there were probably more pressing problems. From today's point of view, that was rather awkward, the LIGO detectors could also have been in the L√ľneburg Heath.

Herbs: What was then built in Germany was a technology test platform, GEO600, which you can find in Hanover on the edge of an apple orchard. How important was it to get there to optimize the LIGO detectors to such an extent that they could ultimately actually detect the gravitational waves?

Danzmann: Well, the essential step was from Initial LIGO to Advanced LIGO, that was a five-year upgrade that we were talking about. Within five years, the original LIGO detectors were literally gutted, there wasn't much left, and new technology was established. We are very proud that most of this technology came from us.

Herbs: The lasers, for example, are manufactured in Hanover.

Danzmann: Yes, they were manufactured and delivered here, but there are also many others, some of which go into great technological detail. I think that is going too far to explain.

Herbs: It's about vibration-damped mirror suspension, clever evaluation strategies for interferometer signals and all such laser-optical tricks.

Danzmann: Yes exactly.

"This price is also our price"

Herbs: In other words, what will you take with you from this day today - the price is okay and part of it ends up with you because you were significantly involved.

Danzmann: That's what it feels like. This price is also our price. And that's the way it is, you have to concentrate. There is a lot of discussion about whether the Nobel Prize should not be awarded to collaborations, as is possible with the Nobel Peace Prize. It's a double-edged sword - the Nobel Prize, you have to see, also fulfills another function: It's the only time of the year when people pay attention to science. The world is loud and if you want to be heard you have to be louder than the rest of the world. He has to fulfill this function, and people need heroes, and heroes have to have faces. And these three people today, they have faces that people can identify with. If you give that to an anonymous collaboration, it'll fizzle out. I don't think that would have the same effect on the public.

Herbs: Now at least all the listeners on Deutschlandfunk are listening to you today, what would you say to them, what should everyone know about gravitational waves?

Danzmann: Most of the universe is dark, everyone should realize that. Over 99 percent of our universe is dark and will never be detected with light or any kind of electromagnetic waves. But everything is subject to gravity, and everything that is subject to gravity and moves emits gravitational waves. It is as if we have been given a new sense organ. We have tramped deaf through a dark world and occasionally saw a few flashes of light. Now we can hear the universe and that will give us a whole new universe. This is just the beginning of a thriving gravitational wave astronomy.

Herbs: Says Karsten Danzmann, Max Planck Director in Hanover.

Statements by our interlocutors reflect their own views. Deutschlandfunk does not adopt the statements of its interlocutors in interviews and discussions as its own.