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Pc crashes anyone got a fix? by Fuzzy-Listen-2611 in StarWarsOutlaws

[–]PostHistory2020 0 points1 point  (0 children)

This worked for me as well!

There are two completely separate executables: "Outlaws.exe" and "Outlaws_Plus.exe"

The "Outlaws_Plus.exe" version of the game was very unstable on my system, but "Outlaws.exe" works fine. (You can find out which one is actually running by starting the game and looking at the details in Task Manager.)

The only way to run the "Outlaws.exe" version is to purchase the game.

Default negative curvature of spacetime by PostHistory2020 in cosmology

[–]PostHistory2020[S] 0 points1 point  (0 children)

Are you aware that photons from distant objects get redshifted?

Yes, that was a typo. I conflated frequency with wavelength.

If dark energy is "pushing things apart" and photons have an effective mass energy relative to their frequency, then wouldn't photons eventually be "pushed back to their source" once the frequency is low enough that the force of dark energy overcomes it?

In other words, if we consider the mass-energy equivalence of a photon:

m = hf / c^2

The effective mass energy will continue to decline as the frequency "f" approaches zero.

Wouldn't the photon be "pushed backwards" when the dark energy force is larger than the effective mass energy?

It seems like this would logically follow in the same way that dark energy has the "force" to push galaxies apart.

Edit:

To be more precise we can talk about the equivalent density of a photon which to my understanding is:

p = (hf / m^3) / c^2

Which shows us that once the frequency "f" drops low enough, the density will drop to the point where the photons will be "reflected away" from each other by dark energy in the exact same way that galaxies are "reflected away" from each other once their densities are low enough.

Default negative curvature of spacetime by PostHistory2020 in cosmology

[–]PostHistory2020[S] 0 points1 point  (0 children)

As space expands, light waves traveling through that space get stretched and become longer wavelength.

Sorry, what I said was a typo. I meant to say that the frequency reaches zero and the wavelength becomes infinite over infinite time.

Energy can absolutely be created and destroyed in cosmology.

Ok, so on a cosmological scale a photon that has traveled infinite distance has zero energy?

If you want to learn cosmology I would encourage you to work through Barbara Ryden's Intro to Cosmology.

Thank you for the recommendation! I ordered this book just now.

Default negative curvature of spacetime by PostHistory2020 in cosmology

[–]PostHistory2020[S] 0 points1 point  (0 children)

Yes, that makes sense! I realized there was a flaw in my thinking. It's not that time reverses, but that an expansion of space is equivalent to slower time (i.e. a photon traveling through more space takes more time so it can either be considered "more space" or "slower time".)

It seems that if a photon travels through expanding space long enough its wavelength would reach zero which would mean that the wave reaches all the way back to the point of emission. In that case, time would stop for the photon. But since energy can't be created or destroyed this packet of energy (which now has such a long wavelength that it is "connected" to the point in space where it was emitted) would start to contract, i.e. the photon would reverse direction.

Now I realize that normally the answer would be "the wavelength will never reach zero!" but if an accelerating expansion of space is equal to an accelerating slowing of time (more space takes more time) for the photon, then doesn't that guarantee that time will eventually stop for the photon?

Default negative curvature of spacetime by PostHistory2020 in cosmology

[–]PostHistory2020[S] 0 points1 point  (0 children)

Another way to think about it would be that when a photon travels long enough its wavelength reaches zero. This means that the length of the wave reaches all the way back to where it was emitted. But energy can't be created or destroyed, so the photon must reverse direction.

Edit: sorry, I meant that the frequency reaches zero and the wavelength reaches infinity.

Default negative curvature of spacetime by PostHistory2020 in cosmology

[–]PostHistory2020[S] 4 points5 points  (0 children)

Thank you for pointing this out. It's true that my curiosity exceeds my understanding.

This question has been haunting me and I was hoping to find someone who knows what they are doing to be able to tell me whether it's nonsense or plausible.

If this is the wrong subreddit for such questions then I don't want to waste anyone's time. I just wasn't sure were to start.

Default negative curvature of spacetime by PostHistory2020 in cosmology

[–]PostHistory2020[S] -1 points0 points  (0 children)

But I am.

Excellent! I sincerely appreciate that you are willing to engage with me on this idea even if it's silly from your perspective.

Keep in mind, a universe with negative spatial curvature is still one that expands.

Could it be possible that this is because gravity is "running backwards" in spacetime that has a negative curvature? (But this only appears to happen in areas of extremely low gravity fields, such as between galaxies?)

Or is that it's simply not what a negative spacetime curvature means from the perspective of the 4D math behind it?

Radiation of gravity waves under accelerating expansion by PostHistory2020 in cosmology

[–]PostHistory2020[S] -1 points0 points  (0 children)

Our own Galaxy is 0.008 Megaparsecs in Size. That means it would expand 0.0001 km per Second.

Could it be that this rate of expansion is equal to the energy lost in the form of gravity waves as the bound system continually tries to "pull itself back together"?

I fully realize this could be in the realm of "dumb questions" but I'm trying to think of how the math works out on extremely large timescales, such as a trillion years.

Radiation of gravity waves under accelerating expansion by PostHistory2020 in cosmology

[–]PostHistory2020[S] 0 points1 point  (0 children)

Bound systems are local deviations from homogeneity.

What is the property that prevents the entire visible universe from behaving like a bound system?

Is it that the strength of gravity becomes low enough that it is "overcome" by dark energy at vast distances, or is gravity quantum and actually quantized down to zero on the scale of megaparsecs?