Astronomy and Space

[Typhoon]

Time to dust off those lead-foil hats?

Space Weather | The Worsening Cosmic Ray Situation

[Typhoon]

And I shall call him "Steve".

NASA | Mystery of Purple Lights in Sky Solved With Help From Citizen Scientists

nqF3AtEkFEU

[Typhoon]

PRL | Cosmic Instability Could Have Created Dark Matter

A proposed instability in the Higgs field could have seeded the Universe with primordial black holes that now serve as dark matter.

[Nonc Hilaire]

And I shall call him "Steve".

NASA | Mystery of Purple Lights in Sky Solved With Help From Citizen Scientists

nqF3AtEkFEU

Disproof of flat earth theory

[noddy]

[noddy]

[Typhoon]

Siegel | General relativity passes its first extragalactic test

[Typhoon]

While one's waistline may be expanding, it's not due to the expanding universe.

You don’t expand just because the universe does. Here’s why.

[Typhoon]

Nature | General relativity verified by a triple-star system

Einstein’s theory of gravity — the general theory of relativity — is based on the principle that all objects accelerate identically in an external gravitational field. A triple-star system provides a stringent test of this principle.

[Mr. Perfect]

Here's the the threshold. The SM, SR, and GR have been repeatedly tested experimentally and have passed all tests at the 5 sigma level or better.
Your personal disapproval is not sufficient.

Not even wrong.

This is an atheist

dbm3M9Bz4RE

[Typhoon]

Here's the the threshold. The SM, SR, and GR have been repeatedly tested experimentally and have passed all tests at the 5 sigma level or better.
Your personal disapproval is not sufficient.

Not even wrong.

Yes, that sums up your mass of misunderstandings.

This is an atheist.

Why would this individual's metaphysical views be relevant?

dbm3M9Bz4RE

He gets it wrong at the start. Hubble was the first to observe and report that the universe is expanding.
Hubble was initially unaware that this observation had already been predicted by solutions of the general relativity [GR] equations.

In 1922, Alexander Friedmann derived his Friedmann equations from Einstein's field equations, showing that the Universe might expand at a rate calculable by the equations.The parameter used by Friedmann is known today as the scale factor which can be considered as a scale invariant form of the proportionality constant of Hubble's law. Georges Lemaître independently found a similar solution in 1927. The Friedmann equations are derived by inserting the metric for a homogeneous and isotropic universe into Einstein's field equations for a fluid with a given density and pressure.

To sum up, GR predicts an expanding universe. This has been tested repeatedly and the best current measurement of the Hubble constant is 73.52±1.62 [km/s]Mpsc.
So GR has passed this and all other tests to date.

The next obvious question to ask is what happens if we run the clock backwards in time. The GR equations give a spacetime singularity. The problem is that at the extreme energy densities of the early universe, quantum effects, according to our current understanding, become important and, as yet, no one has developed a theory unifying the classical GR equations with quantum field theory. This despite decades of intense effort. This is the fundamental problem, that the earliest times of the universe is a region wherein classical GR is no longer sufficient. By rough analogy, just as Maxwell's equations of EM are not sufficient to describe experimentally observed quantum effects.

However, we do have observational evidence of the early universe, the cosmic microwave background radiation to provide clues.
Various ad hoc models, which are add-ons to GR, have been proposed to explain these observations: Inflationary Big Bang, the Bouncing Universe, etc.
All purport to address such issues as flatness and CMB uniformity.
The merits and problems of these various models is an issue of great debate in the astrophysics community.
To confuse these models with GR is a common mistake made by would be amateur critics who have not bothered to inform themselves.

The "magnetic monopole problem" arises only if one assumes so-called Grand Unified Theories [GUTS] exist in nature.
However, such models also predict proton decay and most have been ruled out by experiments.
As an aside, the Inflationary Big Bang model was first developed to address the "magnetic monopole problem", before most GUTs were ruled out by experiment.

[noddy]

https://www.cbc.ca/news/technology/12-n ... -1.4748585

12 new moons discovered around Jupiter
Brings Jovian moon count up to 79, the most in the solar system

pfft, those astronomers cant even decide how many moons Jupiter has. madness.

[Typhoon]

Quanta | Troubled Times for Alternatives to Einstein’s Theory of Gravity

New observations of extreme astrophysical systems have “brutally and pitilessly murdered” [many] attempts to replace Einstein’s general theory of relativity.

[Miss_Faucie_Fishtits]

People don't like the Einsteinian Relativity Theorems because they thwart the easy-peasy simple minded fun of a science fiction future. Things like time travel, going faster than the speed of light and anti-gravity......'>........

[Typhoon]

People don't like the Einsteinian Relativity Theorems because they thwart the easy-peasy simple minded fun of a science fiction future. Things like time travel, going faster than the speed of light and anti-gravity......'>........

As good an explanation as any I've read.

[Typhoon]

Siegel | Is Spacetime Really A Fabric?

Spacetime tells matter how to move; matter tells spacetime how to curve.

~ John Wheeler

[Doc]

Bose Einstein condensate in micro gravity experiment explained.

a488sf7vK24

[Mr. Perfect]

Bose Einstein condensate in micro gravity experiment explained.

a488sf7vK24

"95% of what surrounds us continues to be a mystery" lol no $#! award of the century.

[Mr. Perfect]

People don't like the Einsteinian Relativity Theorems because they thwart the easy-peasy simple minded fun of a science fiction future. Things like time travel, going faster than the speed of light and anti-gravity......'>........

As good an explanation as any I've read.

People just think it doesn't make sense. And they have no reason to believe otherwise, it's never taught properly.

[Typhoon]

Bose Einstein condensate in micro gravity experiment explained.

a488sf7vK24

"95% of what surrounds us continues to be a mystery" lol no $#! award of the century.

Unlike dogma, at any given time in science there are more open questions than answers.

Addressing them is how progress was and is made.

[Mr. Perfect]

I think I finally figured out the problem with Einstein relativity, until the quantum thing gets worked out there isn't much reason to bet invested in it, because the unifying theory will likely prove everything wrong.

[Typhoon]

I think I finally figured out the problem with Einstein relativity, until the quantum thing gets worked out there isn't much reason to bet invested in it, because the unifying theory will likely prove everything wrong.

To figure out that something is wrong, one should first have some understanding of the topic.

QM effects in GR are thought to become important in regions of very high curvature, such as in the region of a black hole.

Outside of black holes, curvature in the universe is too small for QM effects, classical GR works. GR has been repeatedly tested and passed all tests to-date.

[Typhoon]

Physics Today | A record-setting Eddington experiment

An amateur astronomer improved on the famous 1919 experiment after collecting data during the Great American Eclipse.

[Typhoon]

Backreaction | What does the universe expand into.

[Typhoon]

APS | Weak Lensing Becomes a High-Precision Survey Science

Analyzing its first year of data, the Dark Energy Survey has demonstrated that weak lensing can probe cosmological parameters with a precision comparable to cosmic microwave background observations.