Recent content by chronon

Part of the trouble is that such sites aren't considered respectable enough to mention on Physics Forums, but I think that Bad Astronomy and Universe Today Forum probably is . That has an 'Against the Mainstream' section.

If you take a sphere of matter in a homogeneous universe then Gauss's law says that a body on the edge will experience a force towards the centre. Hence all matter will tend to collapse together.

You seem to want to have your cake and eat it too. Isaac Newton supposed the universe was unbounded, but static because gravitational forces canceled out, (so Gauss's law didn't apply). You seem to want to take this universe, but then not have gravitation cancelling out when it affects light.

I think part of the problem is that as a nonscientist she sees 10000 years as a longgggggggggg time, but as far as basic physics is concerned it just isn't. A long time in this context would be more like 10^40 years Suppose I could put myself into suspended animation and set to wake in 10000...

I've a list of books and papers related to wormholes at http://www.chronon.org/books/wormholes.html

I'm arguing that general relativity says that the redshift is due to galaxies getting further away, and can't be explained by gravitational redshift in a static universe. (Note that the OP was talking about expansion rather than acceleration of expansion; there seems to be a separate...

Gauss's law is not nullified, and the attraction between distant galaxies does not cancel out. That is why the density of matter in the universe causes a deceleration of the expansion. No it does not rely on "expanding space". Expanding space is just used to try to give an intuitive picture of...

I think if a philosophy student wrote that in an essay it would deservedly be pulled to pieces. What evidence has she that 'Science' assumes its finding to be definite. And you really don't want to bring probability into it. Do you know how much philosophers argue about probability and what it...

You can argue in two ways A) In a homogeneous universe, gravity will balance out, so overall will not have an effect B) A homogeneous spherical shell of matter will have no effect on matter inside the shell. Hence, if we consider a sphere of matter, we think of the matter outside it as...

Feynman had a lot of trouble being a young professor

Olivia Newton-John is Max Born's granddaughter.

If you have a mass M, then the gravitational acceleration at distance r from is will be GM/r^2 towards it, and the acceleration due to dark energy will be αr away from it, where α is a constant of proportionality, so the total acceleration will αr-GM/r^2. You want to know where these cancel...

The gravitational force between the masses decreases as the square of the distance between them, while the force due to dark energy is proportional to the distance, so that their ratio goes as the cube of the distance.

Actually, I can see a problem with my estimate. It implies the distance at which gravitational attraction and dark energy repulsion goes as the cube root of the mass of an object, so for the Milky Way (mass ~ 2E42 kg ) they would balance at about 2 million light years - about the distance to...

That doesn't look right, the units should be time^-2. Assuming that it means 2 x 10^-35 s^-2 gives r^3=6.674 E-11/2E-35 =3.33E+24, so r=1.5E8 metres - half a light second.