Kevin's Watch

Zarathustra wrote:Michio Kaku speculates in THE PHYSICS OF THE FUTURE that if we can somehow harness dark energy, it would enable nearly "magical" power like anti-gravity, ushering in an new era of physics and technology.

Manfred Mann once sang, blinded by the light ... revved up like a duece ... another runner in the night. Which is really kinda interesting when you think about it's relationship to dark energy. At least to my understanding.
Einstein said that space is curved, causing light to bend around the sun. It stands to reason that light from a lampost at a distance of several metres must also bend, around dark energy. If it didn't, wouldn't any light source in the entire universe blind?

Maybe with the methods of calculations the total mass of the universe.
Our answer is 42.
Would say allot about our methods of science.

Lazy Luke wrote:Manfred Mann once sang, blinded by the light ... revved up like a duece ... another runner in the night.

SMH

What's a duece?

peter wrote:What's a duece?

Most likely it's referring to a Ford car---same car the Beach Boys sang about.
One of the original "hot rods."

[[someone once told me the word also refers to the Devil for some reason? I never hunted that down to check...but it makes more sense in context if the first is correct]].

Vraith wrote:

[[someone once told me the word also refers to the Devil for some reason?].

Merriam-Webster places the word used as early as the 15th century: The Devil, as in "bad luck".
Which could be to do with tarot.

peter wrote:On that, once while traveling to Sri Lanka I got sidelined to Abu Dhabi in mid July and determined to make the most of my 24 hours in a new country headed toward the exit of the hotel I'd been allocated. The fellow at the reception desk looked at me with a mixture of pity and condescension as I crossed the foyer and said "You don't want to go out there." I noticed that the street outside was all but empty - unusual for midday I thought - but proceeded with a knowing smile that said " I'm British you know; I hope I can stand a bit of sun on my head". I stepped through the doors crisply attired and thirty seconds later returned through the same looking like the proverbial guy who crawls out of the desert. The sheer force of the sun that day was incredible! I feel I can say without in any sense of hyperbole that the moment I stepped outside it slammed into me like a sledgehammer!

On the clue front .....mmmmmm........

TSP'sB

(And if I'm correct there are two of them!)

(Gosh, that last bit's good, though I say it myself! )

I thought Lord Foul would be similarly effected but in his favour, it was winter

The behaviour of dark energy depends on what kind of universe you live in.

If your universe expands to a point where its density drops below what's called the critical density, your universe will continue to expand. In an expanding universe dark energy is repulsive - the farther away things are, the faster they will move away from each other.

If the density of your universe does not drop below the critical density, your universe will only expand so far before beginning to contract. In a contracting universe dark energy is attractive - the farther away things are, the faster they will move toward each other.

If the density of your universe is equal to the critical density your universe will continue to expand, but at an increasingly slower rate that asymptotes toward zero.

Q) Where does the dark energy get its energy from?

A) Matter.

The energy density of dark energy is the lowest energy density an event in a universe can possess - the energy of quantum fluctuations of the vacuum of space.

The energy density of dark energy is consistent at all points in the universe, unlike matter.

The expansion will continue and the matter in the universe will make an increasingly smaller and colder contribution to the mass/energy content of the universe, which is already dominated by dark energy.

Eventually, the matter in our expanding universe will be so cold and devoid of energy that there'll be nothing left to power the dark energy.

At this point, the universe will have reached its coldest possible temperature (Gibbons-Hawking temperature). This will be the last moment our universe retains the dark energy density we've known and loved since it was about a trillionth of a second old.

If the universe continues to expand, the energy density of the vacuum will drop. This will change everything about the universe we live in. A different vacuum expectation value (VEV) of the universe means a different universe with different constants of nature.

A lowering of the vacuum expectation value (VEV) of a universe could be described as a quantum tunnelling event in which a volume of spacetime tunnels to a lower VEV.

Also known as a big bang!

FindailsCrispyPancakes wrote: Eventually, the matter in our expanding universe will be so cold and devoid of energy that there'll be nothing left to power the dark energy.

At this point, the universe will have reached its coldest possible temperature (Gibbons-Hawking temperature). This will be the last moment our universe retains the dark energy density we've known and loved since it was about a trillionth of a second old.

Well, that part is assuming facts not at all in evidence, and some evidenct to the contrary.

Inflation started first, and caused the big bang...
what we don't know is: did inflation stop EVERYWHERE at that time? Or did it just stop "locally?"---meaning we're a bubble universe among other unrelated ones happening in other locally collapsing parts of the eternally inflating areas.

The other thing is it LOOKS like, maybe, after inflation, in our universe, the dark-energy driven expansion was slower for several billion years, but then re-accelerated. Not to initial-inflation levels, but faster than previously.
And, since we don't really know what it is, it could accelerate AGAIN at some point/for some reason...or it could flip back...or disappear.
Some of those seem more likely than others---but there's a lot we don't know.
We don't even know if the dark-energy-like initial inflation is/was the same/different/same,but different phase... as the current intra-universe dark energy.
But we DO know that the matter/energy of the big bang is not the source/cause/fuel. It's the product/came FROM/after.
[At least I think we mostly sorta know that].

Wow fascinating stuff FCPsand V .. great reads.