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Hyperlatives

No little thing is to small for grandiose words chiseled by some marketing war machine.

Seen on a Lampe Berger anti-mosquito product this morning:

Parfum “Absolu de vanille”

Vanilla Gourmet Scent

Not only is this ridiculously hyperlative, but they also have a different “tint” for the Engish and French version. English reader will notice that the French version sounds more like “Absolute Vanilla”, because that’s basically what it means. Who on Earth paid people to tell their customers that their anti-mosquito drug had a “Vanilla Gourmet scent?”

Let’s not get used to this kind of marketing hyperbole…

Hyperbole in science

In despair, I turned to a slightly more serious text, the first page of this month’s issue of Science et Vie. And here is what I read there about faster than light neutrinos:

Incroyable? Alors là oui, totalement! Et même pis. Que la vitesse de la lumière puisse être dépassée, ne serait-ce que de très peu, n’est pas seulement incroyable, mais totalement impensable. Absolument inconcevable. [...] c’en serait fini d’un siècle de physique. Mais, et ce serait infiniment plus grave, c’en serait aussi fini avec l’idée selon laquelle la matière qui compose notre univers possède des propriétés, obéit à des lois. Autant dire que la quête de connaissance de notre monde deviendrait totalement vaine.

Incredible? Absolutely! And even worse. That the speed of light can be exceeded, even a little, is not only unbelievable, but totally unthinkable. Absolutely inconceivable. [...] This would end a century of physics. Even more serious, we would be done with the the idea that matter making up our universe has properties, obeys laws. This would mean that the quest for knowledge in our world would become totally hopeless.

Whaaaaat? I really don’t like this kind of pseudo-science wrapped in dogma so pungent to be the envy of the most religious zealots. How can anybody who understood anything about Einstein’s work write something like that? Let’s backpedal a little bit and remember where the speed of light limit comes from.

Where does the speed of light limit come from?

At the beginning was Maxwell’s work on the propagation of electromagnetic waves, light being such a wave. These equations predicted a propagation of light at a constant speed, c, that could be computed from other values that were believed at the time to be physical constants (the “epsilon-0″ and “mu-0″ values in the equations). The problems is that we had a physical speed constant, in other words a speed that did not obey the usual law of speed composition. If you walk at 5 km/h in a train that runs at 200 km/h, your speed relative to the ground is 205 km/h or 195 km/h depending on whether you walk in the same direction as the train or in the opposite direction. We talk about an additive composition rule for speed. That doesn’t work with a constant speed: if I measure the speed of light from my train, I won’t see c-200 km/h, since c is constant. The Michelson-Morley experiment proved that this was indeed the case. Uh oh, trouble.

For one particular speed to be constant, we need to change the law of composition. Instead of adding speeds, we need a composition law that preserves the value of c. It’s the Lorentz transformation. What Einstein acknowledged with his special relativity theory is that this also implied a change in how we consider space and time. Basically, Lorentz transformation can be understood as a rotation between space and time. And in this kind of rotation, the speed of light becomes a limit in a way similar to 90 degrees being the “most perpendicular direction you can take”. Nothing more, nothing less. Of note, that “c” value can also be interpreted as the speed at which we travel along time when we don’t move along any spatial dimension.

There are limits to limits

Once you understand that, you realize how hyperbolic what Science et Vie wrote is.

First, the value of c was computed as a speed of light, for equations designed for electromagnetism. It was never intended to say anything about neutrinos. We don’t know how to measure space and time without electromagnetic interactions somewhere. So the speed of light limit is a bit like the speed of sound limit for bats who would measure their world using only echo-location. It doesn’t necessarily mean nothing can travel faster than light, it only means that no measurement or interaction based on electro-magnetic interactions can ever measure it. I have tried to elaborate a bit on this in the past.

Second, Einstein revised his initial view to include gravity, and this made the world much more complex. Now space-time could be seen as modified locally by gravity. Now imagine how solid your “90 degrees is the most perpendicular direction” argument is if you look at a crumpled sheet of paper. The reasoning doesn’t mean much beyond very small surfaces. Remember that in the neutrinos experiments, we are in a very complex gravitational environment (mountains, …) and you’ll see that this “crumpled sheet of paper” analogy may not be so far off.

In short, it we find conditions where something appears to travel faster than light, it is exciting, it is interesting, it is worth investigating, but it’s certainly not the End of Science as Science et Vie claimed. Let’s not get used to this kind of crap.

Blog-o-pictures

I found this blog thanks to this entry about Russian retro-futuristic art.

But truth be told, I prefer some older posts even better.

Also, one about Buran, the ill-fated russian space shuttle…

Why we need to go into deep space


An interview of A.C. Clarke reminded me of a topic I wanted to write about for a long time: why do we need to gain the ability to go into deep space?

50 years in space

During the first 50 years of space exploration, we have sent many satellites and, more importantly, developed a whole economy around space flight. Recently, private companies have entered the fray. Sir Clarke mentions the Google Lunar X-Prize foundation as one of our hopes to get back to the moon.

The current state of our space technology is largely due to many historical accidents, including World War II and the following competition between the Soviets and the Americans for the best long-range ballistic missiles. In the interview, Sir Clarke recalls Bainbridge’s observation that we were not necessarily due for space travel yet:

As William Sims Bainbridge pointed out in his 1976 book, The Spaceflight Revolution: A Sociological Study, space travel is a technological mutation that should not really have arrived until the 21st century. But thanks to the ambition and genius of von Braun and Sergei Korolev, and their influence upon individuals as disparate as Kennedy and Khrushchev, the Moon—like the South Pole—was reached half a century ahead of time.

Despite what may have been an early start, or maybe because of it, we only explored the immediate neighborhood of Earth. The initial rate of progress (and, in retrospect, pretty wild risk taking) led many science-fiction writers to confidently predict the colonization of the solar system by 2100. The chances of this actually happening now seem a bit more remote than in the 1970s. While we went to the Moon and back, we did not establish any permanent base there.

Scarcity of resources? Not in the solar system

The first step beyond that is to do for the solar system what happened for Earth orbit, which is developing some kind of successful economic model of space. One requirement for this to happen is to lower the cost of space launches, and our best bet for that so far is some kind of space elevator.


Such a technology would also lower the cost of satellite launches, but to me, that’s not the main point, and it is also not all-good thing knowing how much space junk there already is. I do not entirely share Stephan Scherer’s optimism:

50 years after Sputnik, Space below the geostationary orbit has become quite crowded. Fortunately, it is still wide enough

The main point of solar system exploration, as far as humanity is concerned, is really to find useful stuff there, like hydrogen, water, and who knows what else would become useful. Resources that are scarce or, at least, limited on Earth may be available in vast quantities out there, that much is certain. What is not certain is that we could ever lower the cost of exploiting this bounty to a point where it would make sense at all.

But even the solar system is only the beginning…

Deep space vs. Local space

Given our track record in the past 50 years, it may seem premature to talk or think about deep space exploration. First of all, let me explain that by “deep space”, I am referring to space beyond the solar system, warp drives and this kind of far-fetched stuff.

Why do we need that? Well, it’s simply a matter of not taking chances with the survival of our species. On a cosmic scale, there are just many events that could wipe out the entire human race. And, unlike a few, I do not consider this a good thing.


Many of these so-called extinction-level events (ELE) could impact the whole planet. The most well-known type of ELE is an asteroid impact, something so widely known that it even received the Hollywood treatment.

The problem is that it’s not just the whole planet. Some large cosmic events could easily impact the whole solar system. Many cataclysmic scenarios have been imagined, like a gamma ray burst a little bit too close, and in some cases the Earth’s magnetosphere might be insufficient to protect us, while the rest of the solar system would become even more hostile than it currently is.

Are we alone?

Another reason that is always behind everybody’s mind when we talk about space travel is: are we alone in the universe? In that respect, I find Sir Clarke’s comment in the interview highly illogical:

I have always believed in life elsewhere in the universe (though I don’t agree that some are visiting us secretively in flying saucers).



To me, it is quite illogical to believe in something while at the same time dismissing the only “evidence” there is about it, irrespective of how weak that evidence is. There is simply no better reason to believe in intelligent life out there than witness reports that seem hard to explain otherwise.

Sir Clarke’s position is about as logical as believing that one can win the Lottery, but that any testimony of alleged winners must be a big fraud.

Standards of skepticism are too low

Don’t get me wrong: it is possible, even likely, that the majority of this evidence is crap, and one cannot even rule out that all of it is fabricated. But in reality, most “debunking” sites are not more convincing than the believer’s sites, and don’t hold themselves to any stricter standard of analysis. It’s belief against belief, generally with a strong dose of the other guy is stupid ad-hominem rhetoric.

The real reason most scientists don’t believe in UFOs of extra-solar origin is that we have no science that would allow it. Einstein proved that there is an absolute speed limit in the universe, the speed of light, and we don’t know how to go over that speed limit. As far as we know, it’s impossible for any material object to even reach the speed of light. If Einstein is right, then there can be no extraterrestrials from other solar systems in our backyard, it’s really that simple. Interstellar travel based on what we know will never allow a human voyage to a remote star. And for that same reason, it also precludes the visit of biologically similar organisms.

How to cross the light barrier?

What if Einstein was wrong? It is not a stupid question. A few serious scientists have given it a try. It takes some humility to admit that there are still a few things we don’t know about the universe. Lord Kelvin’s famous quote is a mistake not to be repeated again:

There is nothing new to be discovered in physics now, All that remains is more and more precise measurement.

This does not mean we can accept anything. Einstein cannot be too wrong. His theory has been verified over and over again. So the solution is not to be searched by trying to add more fuel to rockets so that they break the light barrier. That simply won’t work. Clearly, we need some kind of breakthrough, something more subtle than brute force.

Maybe a new understanding of the structure of space-time would help, but based on my personal experience, even that may not be sufficient. As far as I can tell, my own “demolition” of space-time only made Einstein’s limit more solid, instead of weakening it. One does not need space-time if all the properties we attribute to this “background” can instead be shown to be properties of electromagnetic interactions. No space-time, great! Properties of electromagnetic interactions, not so great: the speed of light limit comes back with a vengeance. How can you ever hope to go faster than light if time, space, and the relations between them are actually defined by light itself? (For the most curious minds, it’s spelled out in section 3.2 of the article).

On the other hand, looking for a breakthrough does not mean that current space research is useless, on the contrary. Even if today’s automobiles rely on a propulsion system that would have seemed very “improbable” to the average middle-age horsecar driver, a lot of the technology developed back then remained useful, including: the wheel, the seat, roads, maps, and so on. It is very likely that even if we invent some new and fancy way to cross interstellar distances, we will still need space suits or protection against radiation.

Can it be done at all?


The only real question is whether the quest is futile or not. Can interstellar propulsion be done at all? And here, I take exactly the opposite point of view compared to Sir Clarke.

Based on whatever little evidence we have, I would give it a pretty good chances, precisely because in-depth analysis of the UFO phenomenon cannot really explain some cases other than using some hypothetical intelligence driving some apparently mechanical object with a behavior that, as Sir Clarke would say, is so advanced as to be indistinguishable from magic.

Let’s now assume that there is a good chance we can do it. The question in that case is: how? And I regret to say that my own hobby research did not bring me any closer to answering that question.

Categories: Physics, Space, UFOs

Do we need to go into space?

An article in Cosmos argues that we need to go into space. I sort of agree with the points being made in that article, except with one little caveat. At this point, we still don’t know with any certainty if we can go into space to achieve the objectives given there.

Being able to travel into space does not mean being able to do it in an economically or politically viable way. What if the energy cost means that we are forever limited to sending small scout ships? What if the universe is already so populated that we would bump into other civilizations as soon as we venture out?

Categories: Science, Space

Towards the privatization of space

SpaceX did their second test flight on March 21st:

Categories: Space
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