Neutrinos from CERN to Gran Sasso Respect Cosmic Speed Limit

http://press.web.cern.ch/press/PressReleases/Releases2011/PR19.11E.html

by mvanga • 14 years ago

56 26 14 years ago

press.web.cern.ch

taligent• 14 years ago

“Although this result isn’t as exciting as some would have liked,” said Bertolucci, “it is what we all expected deep down. The story captured the public imagination, and has given people the opportunity to see the scientific method in action – an unexpected result was put up for scrutiny, thoroughly investigated and resolved in part thanks to collaboration between normally competing experiments. That’s how science moves forward.”

Couldn't agree more. Whilst there has been a lot of criticism from the science community it was wonderful to experience a bit of drama and excitement.

God knows everyone is looking for something/anything hopeful to distract from the endless bad news.

okamiueru• 14 years ago

Really? Has there been that much criticism from the science community? I though everyone with respectable opinions thought it was handled exactly like proper scientists should have handled it.

OPERA had unexpected results contradicting the status quo of our understanding of fundamental physics. They did everything they could to determine and correct and calibrate possible errors. They published the results and methodology in hopes that their peers could either help them understand what went wrong, or confirm it. An they did (the former).

I saw it as the science community at its finest. Sure, there was a lot of skepticism and disbelief in the accuracy/correctness, but that is part of the game. You don't take things at face value, and you don't ignore unexpected results.

-----

So, I don't have any objection to what you wrote, but, is my impression wrong?

atakan_gurkan2• 14 years ago

There has been enough criticism from scientific community at large and more importantly from within the OPERA collaboration that their spokespeople resigned from their position.

Not much of that criticism coming from respectable scientists made it to mainstream media, though. I presume that is because they did not want to show a "holier than thou" attitude openly. But internally a lot of people thought "they must have done something wrong" and after they found the error "what were they thinking?".

I think your impression is wrong, but very understandable unless you interacted with people offering criticism directly or semi-directly through one or two persons.

planetguy2• 14 years ago

In an ideal universe I think they did everything right. On the other hand, knowing what we know about the state of the popular press and the imagination of the internet it might have been worth being a little more careful to make it clearer that this is probably just an experimental error.

rbanffy• 14 years ago

> I though everyone with respectable opinions thought it was handled exactly like proper scientists should have handled it.

Not all criticism towards science comes from people with respectable opinions. In fact, most criticism towards the scientific community comes from people who have nothing but the most tenuous grasp on what science actually is and, more often than not, to defend a specific agenda.

ck2• 14 years ago

I hope someday they can explain why 186282 miles per second is the limit in the first place.

Cushman3• 14 years ago

c is 299,792,458 m/s only because the meter is so defined; it makes just as much or more sense to say that the speed of light is 1, and this is where we get the Planck units.

From this perspective, it becomes obvious that the question, "Why is the speed of light one unit length per unit time?" is an absurd one. There is no other alternative.

benihana• 14 years ago

Seems tautological. I think what he's asking is, why is there to be a limit to how fast light can go, and he's looking for a better answer than "because there is one." I would love to know why there's an arbitrary speed limit to lights that (from our understanding) spacetime doesn't necessarily have to obey.

hartror2• 14 years ago

The question isn't absurd from a lay persons point of view and the explanation falls short.

What Cushman means is a number like Pi is always 3.14159265, to us or to hypothetical aliens. Whereas the speed of light can be just effectively represented as 299,792,458 or 1 depending on the units you use.

What you are effectively asking about ck2 is calculation of dimensionless physical constants which are of ratios of like-dimensioned physical constants, for example the fine structure constant. These could in theory be calculated one day without using experimentally derived values . . . maybe.

The wikipedia page on the physical constants has a good run down on this: http://en.wikipedia.org/wiki/Physical_constant#Dimensional_a...

As does: http://en.wikipedia.org/wiki/Fundamental_physical_constant

archgoon• 14 years ago

It's an absurd one? Isn't this question essentially the Hierarchy Problem?

asynchrony• 14 years ago

Have they ever explained why Pi is the ratio of a circle's circumference to its diameter?

qntm• 14 years ago

Same reason two plus two equals four.

leejw00t354• 14 years ago

I worry with questions like this that we may never have a convincing answer. There may be things about the universe that are simply ungraspable.

Jach• 14 years ago

You might find this paper interesting: A Derivation of Special Relativity from Causal Sets--http://arxiv.org/abs/1005.4172

It doesn't answer why c is the value of c, but it's an interesting way to show that there must be an invariant bounding speed limit. It doesn't assume the "existence of space or time, motion, constancy of the speed of light, or the principle of relativity."

atakan_gurkan2• 14 years ago

The numerical value is determined empirically, and as far as I know it is simply a result of our historical choice of length and time units.

The fact that there is a definite speed of light is also a property of nature but there is some "explanation". We know that space and time mix. When you speak of an event you need to state both position and time. When you speak about two events, you need to tell their relative position and time difference as well as a reference frame (by indicating its velocity). This separation of events in space and time will be different for different observers, if they are moving at different speeds. The way you transform this quantity includes a constant. When you write the equations governing the electromagnetic phenomena and require that the results obey these transformation rules, it turns out that this constant is the speed of the electromagnetic waves, which is of course light.

The event separation transformation rule dictates that no information can be transferred faster than this constant, the speed of light. Otherwise you can have two events A & B, where the A can influence B in one reference frame and B can influence A in another reference frame. This would lead to a contradiction.

These are explained much better in standard relativity texts. I'd recommend Rindler's "Essential Relativity" and Thorne's "Time Warps and Black Holes"'s first few chapters.

sp332• 14 years ago

The original generated lots of discussion 8 months ago: https://news.ycombinator.com/item?id=3029922

Neutrinos from CERN to Gran Sasso Respect Cosmic Speed Limit

Related Stories