Dark Matter — "Alternative Gravity" Team Responds

An anonymous reader writes, "Following previous results, an international team of astronomers answers, defending the case for a modification of the theory of gravity. This article presents an alternative to dark matter and states constraints on the neutrino mass. In short, dark matter is still not a necessity, provided that neutrinos weigh 2eV. This is allowed by what we currently know and should be tested in the KATRIN experiment in 2009."

Comments

Anti-dark-matter scientists are like ID scientists

[BadAnalogyGuy]

Look at your night sky. It's a whole shitload of blackness with some stars thrown in. Now consider that there is a form of matter which is very dense and very dark. So dark, in fact, that it doesn't give off any radiation at all. All it does is exert a gravitational pull on surrounding masses, just like everything else in the universe.

It isn't difficult to look up and see all that darkness and think that maybe there's something in that blackness that just can't be seen.

But these guys would have you change the Theory of Gravitation because they can't grasp that maybe there are weird states of matter that exist just outside our physical grasp. They'd rather you believe that neutrinos have mass. These neutrinos that have for eons blasted through us at the speed of light with no interaction at all, they are the cause of the entire universe bending unpleasantly.

If you say that neutrinos have a physical manifestation greater than zero, you're going to also have to explain why these particles exhibit no interaction with anything except for being able to curve the shape of space on a galactic level.

Re:why would matter be dark

[exp(pi*sqrt(163))]

Photons do have mass, since they have energy.

Depending on how you define mass.

But they have zero rest mass.

Correct. As far as we know.

If you stop a photon...

You can't stop a photon.

...it has no remaining mass.

But you can't stop one so this is meaningless.

When you accelerate something to the speed of light...

You can't accelerate something to the speed of light.

...its mass increases infinitely.

How can something's mass increase infinitely? Anyway, it's all moot because nothing can accelerate to the speed of light.

So unless the photon starts with no mass at all, you'd never get to the speed of light.

Whatever! This is all so meaningless.

Re:why would matter be dark

[exp(pi*sqrt(163))]

Some moderator is clearly ignorant of basic relativity.