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New, Higher Measurement of Universe's Expansion May Lead To a 'New Physics' (space.com)
doug141 writes: Astronomers have measured the universe's current expansion rate (a value known as the Hubble constant) at about 44.7 miles (71.9 kilometers) per second per megaparsec (3.26 million light-years). This is consistent with a calculation that was announced last year by a research team, but it's considerably higher than the rate that was estimated by the European Space Agency's Planck satellite mission in 2015 -- about 41.6 miles (66.9 km) per second per megaparsec. The cause of this discrepancy is unclear. "The expansion rate of the universe is now starting to be measured in different ways with such high precision that actual discrepancies may possibly point towards new physics beyond our current knowledge of the universe," a researcher said. Mike Wall writes via Space.com: "The differences in the Hubble constant estimates may reflect something that astronomers don't understand about the early universe, or something that has changed since that long-ago epoch, scientists have said. For example, it's possible that dark energy -- the mysterious force that's thought to be driving the universe's accelerating expansion -- has grown in strength over the eons, members of Riess' team said last year. The discrepancy could also indicate that dark matter -- the strange, invisible stuff that astronomers think vastly outweighs 'normal' matter throughout the universe -- has as-yet-unappreciated characteristics, or that Einstein's theory of gravity has some holes, they added."
What, they were standing on a skyscraper when they measured it?
Sig?
In other news "new independent measure of hubble constant shows possible difference from previous measurement. Many more measurements and peer review and theory to follow slowly. But this won't give clicks and excitement so we'll exaggerate things as much as possible please click please click please click please..."
There's always a chance that both answers are correct, even though they are different. Depending where you look (and how far back in time), the physical laws of the universe *might* be a little different.
Einstein said it : "Then again, E=mc^2 may only be a local phenomenon."
Everyone knows physics attained perfection in 1917. It's a scientific fact.
Please, let's called it settled science. It's important to not waste any more time measuring the universe expansion, we have to realize that unless we stop all energy usage now, the universe expansion will continue unabated until we all die a cold, lonely death. It doesn't matter if our little contribution won't affect anything on the long run, but it will assuage our conscience.
Those are the craziest units I've seen yet for measuring a frequency.
Its speed varies depending on what material it is travelling through and over large distances in space different frequencies of EM travel at slightly different speeds though I can't remember the reason why off the top of my head.
Perhaps this is telling us that Hubble's constant is not a constant.
Why are the SI units relegated to the brackets? We're nerds, we can handle it.
The thing that blows my mind is not that one measurement is higher and another lower, it's just how closely they agree: to less than 10%. This despite the fact that they were arrived at from different instruments and lines of inquiry. The earlier measurement from Planck satellite measurements is derived from measurements of cosmic background radiation. The newer measurement comes from images of gravitational lensing of distant quasars, from the Hubble and Spitzer telescopes. For such a tricky measurements, and such an abstruse topic, I wouldn't have been surprised if they differed by an order of magnitude.* And yet, the agree pretty closely.
Science is really freaking awesome. Sure, assuming that the expansion is universal and constant (i.e., there is only one value for the Hubble Constant, which is hardly a sure thing), you ought to be able to measure the same answer by any experiment designed to measure it, within the experimental error. I ought to arrive at the same value for the gravitational constant, too, whether I experiment using a precision pendulum, or dropping a cannonball from the tower of Pisa (accounting for air friction, of course), or analyze the tides, or by successfully putting a man on the Moon. It doesn't matter who I am, or where I live, or under which government, or what language(s) I speak - it all still works.
* Hubble's own initial estimate was about 10x the current values. For those that are interested, here's a graph of the value of H0, with error bars, through history. [source]
Coincidence - it depends on the units you're using to set c. The Hubble rate has dimensions of 1/t, the formula you gave has units of l^2/t^2.
There once was a stargazer named Hubble,
Who said, "We expand like a bubble!"
But finding the rate,
Was a source of debate,
Contention, dissension, and trouble.
When you are put into the Vortex you are given just one momentary glimpse of the entire unimaginable infinity of creation, and somewhere in it there's a tiny little speck, a microscopic dot on a microscopic dot, which says, "You are here."
> If you want to know about the universe, study your bible. Notice that I said "study" rather than "read".. study is required if you want the truth.
Lol! Because ancient goat-herders knew vastly more about this stuff...
You notice the Bible says nothing about whether neutrinos have mass? I wonder why God chose not to reveal that.
I heard they are black...
What about these 2 possibilities:
1) The rate itself is actually changing.
2) Measurements are affected by the gravity where measured. i.e. distance to a significant mass.
Self-importance and self-indulgence is the root of ALL evil.
There's a good point in that word salad somewhere. Now wipe the rabid spittle off and calm down and have another go.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
Look at galaxy. Measure redshift. Redshift shows that it is moving away. Look at another galaxy. More redshift. Notice that the further the galaxy, the greater the redshift. Galaxies are all moving away from each other, therefore universe is expanding. Really, really simple stuff.
We don't have enough years of data to prove the expansion of the universe.
Yeah. We do. These things are billions of light years away.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
Have these "scientists" ever considered that they were wrong to begin with?
Yeah. That's why they have credibility and you don't.
Now imagine how God feels.
LOL. Yeah. "Imagine" how Tom Thumb feels. Imagine how Cinderella feels. Dumbass.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
I prefer to call his imaginary friend the abrahamic god, going with capitalised 'god' just adds to their narrative (my sky daddy only sky daddy). But yes. The Bible also thinks that pi is 3 which is pretty dumb as well.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.