What is going on at NASA?

09/01/2015

ResearchBlogging.org

As a physicist I have been always interested about experiments that can corroborate theoretical findings. Most of these often become important applications for everyday life or change forever the course of the history of mankind. With this in view, I am currently following with great interest the efforts by the NASA group headed by Harold White.Harold "Sonny" White This work has arisen uproar in the web and in the media as it was come to envision the possibility to realize a warp drive, in the way Alcubierre devised it, and the stars were in the reach shortly. As it is well-known, Alcubierre drive implies exotic matter something that does not appear at hand neither in small nor in large quantity. On the other side, it was indirectly observed in the Casimir effect, a beautiful application of quantum field theory to real life. So, it is rather normal to link warp drive with exotic matter. It should be emphasized that nobody on Earth ever managed it in some way and it is not available at your nearest grocery store. The experiment carried out by Harold White and his group is realized with an interference device using lasers on an optical table. The idea is to observe a modification of space-time, a minuscule one, that would modify the paths of the laser beams. This would be comparable to the realization of the Chicago pile by Enrico Fermi that was the starting point for the Manhattan project. I would like to emphasize that such a laboratory small-scale manipulation of space-time would be a huge breakthrough in physics and would open up the way to a new kind of engineering, that of space-time. So, our hopes for a warp drive would be totally fulfilled.

There is an eager desire to obtain any possible information about the progress of White’s work but, of course, there are a couple of hurdles. The first one is that a scientist needs to be certain before to claim a result and we know very well why from some blatant examples in the last years. Extraordinary claims require extraordinary evidence. Last but not least, Harold White is employed at NASA and some restrictions could be required by the organization he is working with. So, it is really interesting a video appeared quite recently where White claims that the effect is there but further work is needed for confirmation. If you have a hour of your spare time, this video is worthwhile to be seen.

This video is interesting per se because Harold White is talking to his colleagues at NASA. But in the question time happens the interesting fact. A White’s colleague asks him “where is the exotic matter?”:

and here something interesting happens. White seems to avoid the question and admits that they talked before in the office. What is more interesting is what the White’s colleague is saying then unveiling some of the machinery behind the experiment. The colleague says that the experiment could be carried out in some strong coupling regime that makes the magic happen without any exotic matter. White denies and disagrees. We know that he is using strong electromagnetic fields in the interference zone. Indeed, the matter of the behaviour of the space-time in a strong perturbation was studied for cosmological aims by Belinski, Kalathnikov and Lifshitz, the BKL trio. David GarfinkleThis scenario was confirmed by numerical studies by David Garfinkle (see here). I was able to derive it by analysing the behaviour of the Einstein equations under a strong perturbation (see here) in analytical way. So, the chance to study such effects in a laboratory would be really striking and would mean an incredible breakthrough for people working in general relativity and related fields. What the exchange between White and his colleague implies is that this could be already at hand and without exotic matter. All the growing concerns about the work at NASA are then not applicable and a different kind of analysis would be needed. Particularly, Alcubierre drive should be devised in a different way. As a physicist, I am eager to learn more about this and to know the real answer, from the horse’s mouth, to the question “where is the exotic matter?”.

Miguel Alcubierre (2000). The warp drive: hyper-fast travel within general relativity Class.Quant.Grav.11:L73-L77,1994 arXiv: gr-qc/0009013v1

David Garfinkle (2003). Numerical simulations of generic singuarities Phys.Rev.Lett. 93 (2004) 161101 arXiv: gr-qc/0312117v4

Marco Frasca (2005). Strong coupling expansion for general relativity Int.J.Mod.Phys.D15:1373-1386,2006 arXiv: hep-th/0508246v3


Curiosity finds organics but where do they come from?

04/12/2012

NASA logoYesterday, at the meeting of the American Geophysical Union in San Francisco, NASA announced first results from soil analysis performed by Curiosity. Indeed, initially there was an eager expectation about this announcement as some rumors leaked out and somebody told about historical results. Then, all this was teased by NASA but what they announced yesterday was all but disappointing. I followed a real-time chronicle on twitter by Emily Lakdawalla (@elakdawalla and check her blog) that was there in San Francisco and it was really exciting. The main point is that Curiosity indeed has found organics but that people at NASA cannot be sure yet that carbon was not from Earth. Anyhow, the analysis of the soil displayed a rich content and this is indeed a riverbed. Some further analysis are required before to give definitive conclusions about the presence of organics. If you need a short summary you can read this article on The Guardian but Emily should provide a complete account shortly.

CuriosityI would like to spend a few words here to let my readers know what is at stake here. On 1975, NASA launched the Viking probes on Mars. One of the aims of this mission was to perform some experiments that should give evidence of life on Mars. A pair of these experiments turned out  to give favorable results giving such an evidence but the probes failed at finding any organic molecules and so these results were interpreted as due to some other chemical process at work. Indeed, the question is open yet. Should Curiosity find any evidence of organic molecular, the original findings of Viking probes would be vindicated but, more important, one should have a first evidence of life, even if bacterial, on another planet. This is for historical book indeed!


Warp drive at NASA

19/09/2012

ResearchBlogging.org

I am currently a twitter user. One of my followings is Jeri Ryan. She has been Seven of Nine in Star Trek Voyager saga. Yesterday, it comes out of the blue what I read in one of her twits: NASA is developing warp drive! Indeed, Jeri was pointing to  this link. This is a Gizmodo’s post that was describing an effort by NASA to develop warp drive and it seemed like something consistent was in hand. Indeed, this is all true. It is a lab at NASA, Eagleworks, headed by Harold White that is working on a technical realization of the most recent ideas from physics in the area of “spacetime engineering”. This is somewhat of a new term as, so far, no ways were at our disposal to modify spacetime even if, in principle, this is a possibility offered by general relativity. If one would be able to do so, we would have warp drive but also time machines, wormholes and all that. White’s group claims to have found some loopholes in all the hurdles encountered so far in this kind of researches. The most fundamental one is that one needs a huge quantity of exotic matter to get some of these devices work. Nothing that is manageable in practice. So, all this matter was always put in an area of research much theoretical oriented. In a quite recent paper, Stefano Finazzi, Stefano Liberati and Carlos Barceló (see here)  show that Alcubierre drive is unstable with respect to quantum effects: Indeed, if you go faster than light, Hawking radiation will kill you.

So, there are some important difficulties to overcome to change the situation from theoretical to a practical one. One of the Editors of Physical Review Letters, Robert Garisto, commented as follows on twitter:

NASA warp drive story: Not sure which is less plausible, that it’s allowed by physics or that we could implement it if it were.

White’s group claims that they are on the verge to realize an experiment comparable to the Chicago Fermi’s experiment on the nuclear pile. This would imply that they have overcome all the difficulties seen so far in this kind of studies and are able to provide a working realization of the effect. You can find a paper by White here and is worth reading. They can controvert any skepticism by a sound experimental proof.

My view is always the same: As a physicist I have a blind faith on experimental facts and I would like to see accomplished one of my lifetime dreams arisen with that small step by Armstrong on the Moon. NASA is never a disappointment.

Stefano Finazzi, Stefano Liberati, & Carlos Barceló (2009). Semiclassical instability of dynamical warp drives PHYSICAL REVIEW D 79, 124017 (2009) arXiv: 0904.0141v2

Miguel Alcubierre (2000). The warp drive: hyper-fast travel within general relativity Class.Quant.Grav.11:L73-L77,1994 arXiv: gr-qc/0009013v1


The man passed away, the legend will always survive

26/08/2012

Neil Armstrong passed away yesterday (see here and here). He was the first man to put his feet on the Moon. He started all my dreams when I was just nine and that July’s night I was staring at his extraordinary enterprise together with Buzz Aldrin (see here) and Michael Collins on the Apollo 11. Now, I am moved to tears by this but my dreams are still there and his legend will always survive. Thank you very much, Neil!


Curiosity touched down successfully!

06/08/2012

I was excited this morning while I was looking at the last minutes of flight of Curiosity there at JPL. This remembered when I was nine and, with my father, I looked at man on the moon.  This time I was with my sons and we shared happiness with all the people that worked hard for another great success.  Keep up this great job!


Water on the Moon!

13/11/2009

NASA announced today that LCROSS has indeed found water on the moon and in a significant quantity. The announcement is here.

402518main_LCROSS_results3_full

The view of the floor of Cabeus as seen through the LCROSS near-infrared camera. The fresh crater made by the Centaur impact is indicated. Credit: NASA

This is a wonderful result both for the achievement and the technique NASA used. The meaning for the future explorations in space is made brighter by this finding and the reason is that, having significant reserves of water on the moon, building a base for future missions in the solar system is made easier. So, in a situation where funding cuts are the most common actions governments accomplish, such a successful mission proves that smart people always find a way toward the aims. On the other side, we hope that, when economical difficulties in US will be overcome, NASA will be again properly funded to realize the most significant goals in space missions.


NASA shows leftovers of missions on the moon

18/07/2009

There has always been a lot to laugh about skepticism on lunar missions. Today, I apprehend from an article in the New York Times (see here) that NASA released a set of photos from Lunar Reconnaissance Orbiter (LRO) clearly showing leftovers from Apollo missions. They released photos for missions 11 and 14 to 17 (Apollo 13 never landed for an explosion on board and photos on Apollo 12 will be released in the near future). I show here the photo on Apollo 14 taken from New York Times clearly showing the lunar module and its shadow and the most used path by astronauts.nasa_600 I can still remember that night with my father waiting for the landing of the lunar module and Neil Armstrong making his first step on the moon. Most of the choices I have done after in my professional life are due to that exciting night.

Thank you very much, folks!


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