I suggest that there are repelling particles (probably 50% of all matter and antimatter) that cause the expansion of the universe.These particles would mainly have dispersed far from Earth so would be practically invisible to us, but would be very useful if we did manage extract enough to build spacecraft etc.
The difference between the two values is about 9 percent.That sounds like a lot.
https://www.nasa.gov/feature/goddard/2018/improved-hubble-yardstick-gives-fresh-evidence-for-new-physics-in-the-universe..Explaining a Vexing DiscrepancyRiess outlined a few possible explanations for the mismatch, all related to the 95 percent of the universe that is shrouded in darkness. One possibility is that dark energy, already known to be accelerating the cosmos, may be shoving galaxies away from each other with even greater or growing strength. This means that the acceleration itself might not have a constant value in the universe but changes over time in the universe. Riess shared a Nobel Prize for the 1998 discovery of the accelerating universe. ..
"Dark Energy" definition: There seems to be something there doing something, but we have no idea what it is or what it's doing.For that enlightening "discovery", we already know it's accelerating the cosmos, have handed out Nobel's for the "discovery" and yet are still trying to figure out what that "discovery" was or if it's something else entirely. Guess what - there is no Dark Energy, no force, no nada.
If the distance between two points increases it could mean they're moving apart -or- that the space between them is increasing. If light traveling through this region changes frequency, if more distant objects have a greater change in frequency it's because the space is expanding. To instead conclude the source of the light is moving away shows clear ignorance of how light works - like Hubble and his "constant".
"This means that the acceleration itself might not have a constant value" - No kidding. If space is increasing (likely as a Universal constant in gravity's absence just as space compresses in gravity's presence) than the produced space will continue to produce more space, just like bunnies! Thus the more distant an object, the more space between, the more space that's being created and the greater the redshift. However, to calculate the expansion of space we must quantify the compression of light - the blue shift - as it enters our System (solar or galactic) as well as that of the source star or galaxy.
It's not "New Physics" or undefined naivate like "Dark" energy/matter that's needed, but normal physics done right.
Astronomers know this and have worked it out through a variety of measurements. It is the space expanding, which means that things are moving away from each other..
..and since the space itself is expanding the initial Doppler shift is exaggerated as the light travels through expanding space to reach Earth.
The blueshifts you mention generally cancel out in most cases, since there was also extra redshift from leaving the gravity well of the source. That doesn't change the fact that further away objects are more redshifted.
Dark energy is .. a placeholder, but it is needed to explain why expansion is accelerating.
Unless you have a new model of cosmology that can replicate the predictions of GR, but naturally has spacetime with accelerating expansion, then you can't talk about the accelerating expansion and deny the existence of dark energy at the same time.
What you are doing here is equivalent to asserting that every astronomer on this planet is an idiot. Please think before posting. The astronomers know how to do the math. The data shows that expansion is accelerating, and "normal physics" cannot account for the fact that space itself is expanding at an increasing rate unless you add in an extra term such as dark energy.
Quote from: meberbs on 10/25/2018 03:48 amAstronomers know this and have worked it out through a variety of measurements. It is the space expanding, which means that things are moving away from each other..How can you equate expanding space to objects moving?...What initial Doppler shift? Doppler is a result of of photons being re-emitted by a body and the kinetic energy of that body altering the wavelength. Light for a star is not re-emitted and thus has no initial Doppler shift. Any matter in the system which may re-emit has zero kinetic energy as its moving with the star, so again - no initial Doppler shift.
QuoteThe blueshifts you mention generally cancel out in most cases, since there was also extra redshift from leaving the gravity well of the source. That doesn't change the fact that further away objects are more redshifted.Why would there be redshift leaving a gravitational well and blueshift when entering if spacetime is contracting in both places? The "fact" further away objects are more redshifted has nothing to do with actual distance, but the amount of empty space it travels through. Yes - there's relation, but not causation.
QuoteDark energy is .. a placeholder, but it is needed to explain why expansion is accelerating.They could just as easily call it "WTF?", but then it wouldn't win a Nobel.
QuoteUnless you have a new model of cosmology that can replicate the predictions of GR, but naturally has spacetime with accelerating expansion, then you can't talk about the accelerating expansion and deny the existence of dark energy at the same time.Pretty sure I did just describe a new model of cosmology while denying the whimsical fancy of Dark Energy.
QuoteWhat you are doing here is equivalent to asserting that every astronomer on this planet is an idiot. Please think before posting. The astronomers know how to do the math. The data shows that expansion is accelerating, and "normal physics" cannot account for the fact that space itself is expanding at an increasing rate unless you add in an extra term such as dark energy.If astronomers can do math, their data shows normal physics cannot account for expanding space and therefor must add a placeholder like "WTF", then obviously something's wrong. I've thought about it plenty, and before posting, and every astronomer on this planet may be a modern Geocentrist describing the Heavens. "Why do Mars and Jupiter retrograde? - We call that Dark Energy."
There does not need to be a "re-emission" to have a Doppler shift.
1)..There is nowhere in the universe to our knowledge where space is contracting.2)..(Astronomers) know something is wrong, that is why they are looking for new physics. ..You are instead stating contradictory nonsense (like spacetime contracting in some places) that indicates you don't have a clue what you are talking about.3)..Your appeal to qualitative words like "whimsical" only shows that you have no real argument, and makes it appear you aren't interested in a logical discussion
Quote from: meberbs on 10/26/2018 06:28 amThere does not need to be a "re-emission" to have a Doppler shift.Actually, that's exactly what causes a Doppler shift. Fire a laser at an object, stationary or in motion, and the Photons impart force. The force is energy transferred by the Photons - basic physics here, folks. If the object is moving away and is accelerated by photons, the re-emitted (or reflected if you prefer the term) photons will have lost energy and frequency. If the object is approaching and slowed by the photons, the re-emitted photons have gained energy and frequency.
Quote1)..There is nowhere in the universe to our knowledge where space is contracting.2)..(Astronomers) know something is wrong, that is why they are looking for new physics. ..You are instead stating contradictory nonsense (like spacetime contracting in some places) that indicates you don't have a clue what you are talking about.3)..Your appeal to qualitative words like "whimsical" only shows that you have no real argument, and makes it appear you aren't interested in a logical discussionRe1) Considering astronomers have no viable theory of the Universe, nor what's in it - your statement is correct.Re2) Have you dismissed a comment just for opposing conventional theory, even when those theories admit to being ill-informed, and inaccurate? Yet you mandate "new physics" that would be contrary to conventional theory? Hiding ignorance behind "placeholders" like Dark Energy or "new physics" is such an admittance.
Re3) Did you just dismiss an argument because you didn't like an adjective? I object to your use of the word "nonsense" or "qualitative" as it shows you don't have a clue nor interest in logical discussion.
someone who clearly doesn't know basic physics claims GR and runs semantic circles rather than discuss the science.
I'm wrong for not repeating what Astronomers - who know they're wrong - say
Premise: Spacetime flows toward mass. The observed effect is known as Gravity, though there's actually no real force nor fundamental particle of Gravity. Additionally, the effect of mass on spacetime results in a retardation of time -experimentally proven and quantified.
1) Spacetime is stretched as it flows toward mass. Light traveling in, out, or especially through this well will be redshifted. As such, all light we observe is redshifted by our own system as well as redshifted leaving the initial system. Larger systems will be more redshifted due to their mass and the remaining redshift is from empty space's expansion.
5) Spacetime's expansion is a result of the Big Bang. As time passes its expansion rate is decreasing, but only when observed from the 4th dimension. From the 3rd, it appears to be accelerating.
https://phys.org/news/2017-03-expansion-universe-dark-energy.html
Great article and read btw, thank you for sharing.Quote from: colbourne on 03/21/2018 03:08 amI suggest that there are repelling particles (probably 50% of all matter and antimatter) that cause the expansion of the universe.These particles would mainly have dispersed far from Earth so would be practically invisible to us, but would be very useful if we did manage extract enough to build spacecraft etc.Whats the point of suggesting anything with no evidence or work to back it up?
If there are repelling particles they remove the need for dark energy and dark matter.