"He also thinks that the Universe could be filled with 'primordial' dark-energy stars. These are formed not by stellar collapse but by fluctuations of space-time itself, like blobs of liquid condensing spontaneously out of a cooling gas. These, he suggests, could be stuff that has the same gravitational effect as normal matter, but cannot be seen: the elusive substance known as dark matter." (Via The Anomalist.)
If black holes are indeed physically impossible, what happens to wormholes . . . ?
7 comments:
i dont see it as the guy is saying the basic concept of a massive gravitational singularity is wrong...it seems more that he is renaming the concept slightly...
bringing it more in line with all this dark energy/matter theories...
but its all struggling to make sense of a broken system anyway...if they keep ignoring the "wierd" side of gravitics they will never make sensse of what they observe in the universe.
I didn't find George Chapline's explanation of his idea of "dark ernergy stars" at all convincing, at least not as reported on News@Nature. As I understand it, dark energy is basically a repulsive force used to explain the expansive acceleration of the universe). That is, it's a kind of anti-gravity. So wouldn't a dark energy star fly apart from its own internal repulsion? Either that, or the story didn't explain his theory well enough to allow any kind of cogent criticism.
--WMB
If the general relativity theory is correct, would our clocks tick slower or faster on Mars?
Faster, I think. The Earth is moving faster in its orbit than Mars and faster velocity = slower clocks (relativistic time dilation). Plus the earth's gravity well is deeper, and that slows down time a bit too, I think. The difference would probably be in the dozens of nanoseconds range but probably measurable.
BTW, physicists have done experiments with atmomic clocks in orbit to verify relativistic time dilation, so there's no "if correct." It IS correct, at least at the observable scale.
--WMB
Ok, well then how do physicists determine the age of the universe? I mean in order to estimate just how old the universe is, wouldn't they need to have a universal and absolute standard of time?
Nope. The age of the universe is simply equivalent to the maximum distance at which we can observe anything. The best current estimate for this seems to be 12.5 billion light years, so cosmologists consider the universe to be roughly 12.5 billion years old. The universal and absolute standard is the speed of light itself, roughly 186,000 mps or 300,000 km/sec in a vacuum, give or take. Relativity seems paradoxical until you try to figure it out. Then it seems even more paradoxical!
--WMB
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