Transfer of atomic mass with a photon solves the momentum paradox of light

Re:Transfer of atomic mass with a photon solves the momentum... by simonh on Sunday July 02, 2017 @10:01AM (#14682518)

It could be extremely hard. We don't have many good ways to measure how far away objects are in space. In fact the main way we have been estimating distance so far is by measuring red shift. We also have very limited means for measuring the density of the intergalactic medium.

I just don't think we have any good ways to distinguish whether a high redshift is due to the object being very distant or the intergalactic medium in that direction being particularly dense, for most objects.

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Re:Transfer of atomic mass with a photon solves the momentum... by strainer on Sunday July 02, 2017 @10:21AM (#14682595)

I guess the geometry of galactic filaments may be examined for distortions/textures relating to non-standard red shifting. We may see the filaments are bent from our viewpoint in accordance with the presence of voids or other filaments along the way.

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Re:Transfer of atomic mass with a photon solves the momentum... by sandworm101 on Sunday July 02, 2017 @11:15AM (#14682843)

There are some very good ways. Thats how redshifting was proven in the first place. Cephiads (sp), pulsing stars, were used to prove that galaxies were a thing. They give very accurate distances at ranges where redshift is detectable.

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Re:Transfer of atomic mass with a photon solves the momentum... by empath75 on Sunday July 02, 2017 @10:04AM (#14682528)

There are type Ia supernovas that can give precise distances, no?

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Re:Transfer of atomic mass with a photon solves the momentum... by marcosdumay on Sunday July 02, 2017 @11:31AM (#14682921)

They give very precise distances by red-shift calculations.

There's no direct way to measure the distance of very far objects. There's only red-shift and Hubble's Law.

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Re:Transfer of atomic mass with a photon solves the momentum... by FeatureRush on Sunday July 02, 2017 @02:54PM (#14683808)

Wasn't it the other way around? A type of supernovas ("standard candles") were discovered before the expansion and used to discover the expansion? The formula for distance only uses absolute and apparent magnitudes to calculate distance?

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Re:Transfer of atomic mass with a photon solves the momentum... by marcosdumay on Monday July 03, 2017 @11:36AM (#14689008)

Yes, my comment above is wrong. It was the other way around.

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Re:Transfer of atomic mass with a photon solves the momentum... by empath75 on Sunday July 02, 2017 @05:58PM (#14684566)

Yeah they calibrated red shift from standard candles.

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Re:Transfer of atomic mass with a photon solves the momentum... by funnuf on Sunday July 02, 2017 @09:42PM (#14685369)

They use luminosity for SNe Ia.

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