Archive for October 15th, 2017

LIGO COURTROOM DRAMA: Trial Part 10

October 15, 2017

TRIAL PART 10

ON THE WITNESS STAND: Professor Karsten Danzmann (for the Defendants)

VINO MOSCATO (Attorney for the Defendants): Greetings, Professor Danzmann. You are the Director of the Max-Planck Institute for Gravitational Physics, and a major player in LIGO. One of the scientific areas you are concerned with is calibration of the LIGO instrument. My first question to you is this: Is the LIGO instrument calibrated?

KARSTEN DANZMANN: It is.

MOSCATO: And has this calibration been documented?

DANZMANN: It has been extensively documented. It involves painstaking research involving controlled moving of the LIGO mirrors, and noting the LIGO instrument readout corresponding to this mirror movement. This is followed by extensive scientific and technical analysis.

MOSCATO: Is this the kind of technical complexity you were referring to when you told one Wolfgang Engelhardt that LIGO calibration is too complicated to understand?

DANZMANN: Yes. He expected simple or simplistic answers, but they are not often available at the cutting edge of scientific instrumentation.

MOSCATO: Very fine! So you did not intend any slight to Engelhardt?

DANZMANN: Of course not.

MOSCATO: Is the LIGO calibration science Engelhardt wanted to know about all recorded in the public domain? I mean, nothing he would need to understand the calibration procedure has been classified or kept from the public?

DANZMANN: Everything necessary to understand LIGO calibration is in the public domain. Someone capable of understanding this will see that LIGO is a properly calibrated instrument.

MOSCATO: Indeed! It is quite obvious that the Nobel Prize deliberation committee has understood and accepted as valid the calibration. And that is the final imprimatur on the calibration procedure – a kind of certificate of operability. Wouldn’t you say?

DANZMANN: I think it is self-evident.

MOSCATO: Thank you, Professor Danzmann. Your Witness, Ms. Veritas.

ASSUMPTA VERITAS (Attorney for the Plaintiffs): Professor Danzmann, let us stipulate that LIGO calibration is a highly complex and highly specialized area of science and technology. Let us leave that aside altogether. Could you, in very simple terms, describe for the jury what calibration is?

DANZMANN: Certainly. I will be happy to. Consider a situation familiar to all of us. You have been to the doctor’s office and they put you on that stand which measures your height. They lower the sliding angle until it touches your head, and read off the height from the scale on the stand there. Now, how was that scale marked by the manufacturer of the instrument? What they did is build the stand that is now blank – without any markings. So they take an eight-foot length standard, say. This standard has been measured elsewhere to be exactly eight feet long. The manufacturer places this on his stand and makes a mark for eight foot length. Now he can put the standard away and subdivide that length and place marks every foot, every inch, every half-inch etc. This is calibration.

VERITAS: Thank you. And now, staying with your medical analogy, suppose a surgeon has taken out a group of gallstones and needs to measure them. How would he do that?

DANZMANN: I don’t know what they actually use, but a pair of Vernier calipers would do very well. It can measure sizes in the millimeter range and below.

VERITAS: What length standard would be used in calibrating that instrument? Would the eight-foot standard do?

DANZMANN: No. Here they have to use millimeter length standard.

VERITAS: Good. Now back to LIGO. Is it true that in the actual situation of detecting a gravitational wave, the LIGO mirror moves to, or is displaced by, the extent of one ten-thousandth of a proton diameter?

DANZMANN: Yes.

VERITAS: And your highly complex LIGO calibration procedure – does it displace the mirror in this range?

DANZMANN: No. We move the mirror by a distance that is orders of magnitude larger.

VERITAS: So, Professor Danzmann, by what you have explained yourself with regard to length standards, the LIGO instrument was never calibrated for measuring gravitational wave. Do you agree?

DANZMANN: No. You have oversimplified the issue.

VERITAS: What is there to oversimplify? Either LIGO was calibrated using a displacement standard near ten-thousandth of a proton diameter or it was calibrated using a displacement standard orders of magnitude larger. Which one is it?

DANZMANN: It is the larger, but it works for the smaller case also. How it works is much too complicated to describe here.

VERITAS: Have you described the justification for this unheard-of orders-of-magnitude extrapolation in any public document?

DANZMANN: Well, not directly.

VERITAS: Are you saying that this is so complex that trained scientists like Professor Engelhardt who worked at a Max Planck Institute or Dr. De who holds measurement and instrumentation patents cannot understand? Is this the “You do not understand” response for which LIGO has become so famous?

DANZMANN: Well, clearly the Nobel evaluators could understand; and clearly the entire physics establishment could understand. So we are talking about a couple of people disagreeing with a total scientific consensus.

VERITAS: So now we are moving to the Democracy argument. Is that the ultimate arbiter of science?

DANZMANN: Scientific consensus has always been the way science progresses.

VERITAS: For the calibration that you did do, have you presented side-by-side comparison of the mirror displacement trace vs your instrument readout trace. If not, why not?

DANZMANN: We have not. And the answer is too complicated.

VERITAS: Professor Danzmann, I submit to you that – all other faults aside – LIGO was never calibrated for detection of gravitational wave. What calibration you have done is faulty. I submit to you that Professor Engelhardt and Dr. De are the only people on record as having actually understood the LIGO calibration science. I submit to you that all along you have been trying to snow the critics with this complication argument. I submit to you that your vaunted Nobel certification of your calibration procedure is not worth the piece of paper it is written on.

DANZMANN: You are entitled to your views.

VERITAS: Your Honor, I have no further questions.

JUDGE: Any redirect, Mr. Moscato?

MOSCATO: Yes, Your Honor. Professor Danzmann, is it correct that you are a highly decorated scientist, adorned with such distinctions as the Korber Foundation Prize and the Lower Saxony Prize?

DANZMANN: I was given those prizes.

MOSCATO: No further questions, You Honor.

JUDGE: The witness is excused.

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