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Last Week's Announcement About Gravitational Waves and Inflation May Be Wrong
KentuckyFC (1144503) writes "If you've been living under a stone, you might not have heard last week's announcement that astrophysicists from the BICEP2 experiment have found the first evidence of two extraordinary things. The first is primordial gravitational waves--ripples in spacetime from the very first moments after the Big Bang. The second is that these waves are evidence of inflation, the theory that the universe expanded rapidly, by twenty orders of magnitude in the blink of an eye after the Big Bang. But that can only be possible if the gravitational waves formed before inflation occurred. Now critics have begun to mutter that the waves might have formed later and so provide no evidence of inflation. The new thinking is that as the universe cooled down after inflation, various phase changes occurred in the Universe which generated the laws of physics we see today. These phase changes would have been violent events that generated their own ripples in space time, which would look very much like the primordial gravitational waves that the BICEP2 team claims to have found. So the BICEP2 team must rule out this possibility before they can claim evidence of inflation. But the critics say the data does not yet allow this to be done. That doesn't mean inflation didn't occur. Indeed, the critics say this is still the most likely explanation. But until the phase change possibility is ruled out, the result must be considered ambiguous. So put the champagne back in the fridge."
Um also this is one experiment with no confirmation yet. No one else has repeated the results as of yet so how about putting the champagne away until another group of experimenters confirms?
https://www.fsf.org/associate/support_freedom
I think phase changes on a universal scale is an amazing thing to ponder.
This aspect of the story is great as an example of science.
It seems stubborn to hold onto a single interpretation of evidence during pursuit a theory, including the origin of the universe.
Science is the willingness to relegate that evidence to be less significant than what some people want it to be.
When you won't relegate the evidence, then you are practicing faith (in the evidence) instead of science.
You, on the other hand, will burn in the Pit.
At least I'll be warm compared to the frozen wasteland your God has created on Earth.
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
the result must be considered ambiguous. So put the champagne back in the fridge.
Already drank the champagne... Um, my fridge is, er, full, can we use yours?
This is un-provable and wild and rampant speculation. Keep twisting the evidence to support your beliefs, meanwhile I will worship God and be granted life Everlasting. You, on the other hand, will burn in the Pit.
Have you heard the bitchin' news?! I reject your god because I don't need some elitist hipster cloud club. I've had my fill of standing in lines and getting judged at the door in this life, screw doing it again in the next. So, I bought my front-row ticket to the hottest show in Earth because all the good bands and fun people will be there.
You may be interested in my pamphlet, "So, you've decided to go to Hell."
The media hyped this up. The BICEP2 team did nothing wrong.
The world's burning. Moped Jesus spotted on I50. Details at 11.
What really happened was that Wolowitz and Koothrappali rigged the electric can opener to create false postitive results for Sheldon's test equipment. He shouldn't have announced his findings so soon.
Proverbs 21:19
Over the last... long while now scientists have developed a bad habit of getting really excited and presenting findings as concrete, only to get shot down. Besides, doesn't an experiment have to be repeated for the results to be confirmed? Regardless, if the alternate interpretation proves true, I find it no less significant.
It's customary in science to present your findings exactly as they are, with the statistical certainty associated with the findings. They never said their results were confirmed or "concrete", they said their findings confirmed several other theories and that they were highly certain of the results given the known sources of error and the model they were using. You can always come up with other theories that would also fit the observational data: heck, half the point of publishing your data is so the scientific community can look at it and see if you did something wrong, or if there are other interpretations that fit the data better.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
Over the last... long while now scientists have developed a bad habit of getting really excited and presenting findings as concrete, only to get shot down.
I don't recall anyone saying those results were "concrete". I think that a lot of the science skeptics are simply not capable of thinking as a scientist. If you take the political and faith based systems as an example, the person makes up their mind, such as "All liberals are evil" or "The Bible says the entire world was covered with water, so it was, and I'll accept no evidence to the contrary." It is people like that who have difficulty understanding the way the scientist thinks.
The scientist is ready to move onto a new paradigm if the old one quits working. Scientists are human, and therefore subject to the same foibles as everyone else, But in general, the scientist is prepared to change their mind. In other words, scientists have no problem getting excited about something, then saying "Oops - We made a mistake!"
Besides, doesn't an experiment have to be repeated for the results to be confirmed?
When possible. But that doesn't mean that things we cannot reproduce cannot be studied. We really don't want to return to inflationary times in order to reproduce them. That's why we have theories (let us not confuse them with hypotheses)
So in the realm of cosmology, we have theories. We have hypotheses. Does what we predict pan out? Does the formula make a useful prediction.What is the math? Do I have an interesting idea?.
Note that I ran that series backwards, just as we have to do in matters of cosmology.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Scientist are still analyzing the data of ESA's Planck satellite, with first results expected in October this year. This instrument is supposedly sensitive enough to confirm or reject BICEP's results. I guess Planck's team must feel pretty depressed that the potential big discovery of their 700 MEuro instrument is scooped by the relatively small-scale BICEP experiment.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
My question is, do these ACs PURPOSEFULLY misquote this song? By now, everyone should know that the last word in the first stanza is "confidant"; enough people have pointed it out. Or, is this just a 'bot with a fixed text file that is never updated?
I urge anyone interested in these questions to go to Professor Matt Strassler's blog: http://profmattstrassler.com/ . In particular he goes to some length to describe what BICEP2's data might mean.
The world's burning. Moped Jesus spotted on I50. Details at 11.
...as someone said once are human-centered idea, that there are laws obeyed by nature that we can grasp with our minds and that those laws must be unchanging. This is the unspoken assumption, that the models that would explain the physical processes never changed in the course of the evolution of the Universe. I'm beginning to think that such assumption is no different from Newton's "mind of God" that he wanted to know -- we just call it slightly differently.
And how is this claim relevant? If those "laws" have not been unchanging, we may be wasting enormous time and money trying to find out how it all began in a way we imagine has to have happened, ie. producing theories that have no consequence other than to satisfy philosophical questions that we insist must be posed only in a certain way -- and they can't even do that. I hope at least some consequential discoveries and tools will be made along the road.
Another one: "'Scuse me, while I kiss this guy."
This is known as a Mondegreen.
If it weren't for deadlines, nothing would be late.
First, massless particles, like the photon or graviton, don't go past c. They go exactly c. Anything going faster would be a tachyon, which isn't like any of the massless particles we know. BTW, these BICEP2 results seem to confirm the existence of gravitational waves, and thus of gravitons. Otherwise, I would have said "supposed gravitons" or something like that.
There is also the concept of tachyonic fields, which are fields whose particles have imaginary mass. The Higgs before symmetry breaking occurred is an example, but despite their name, excitations of tachyonic fields propagate at or below the speed of light.
In short, you can't accelerate even massless particles past c. Nevertheless, objects can have faster-than-light relative velocities as long as these are acquired via the expansion of space.
.: Semper Absurda
Only in theoretical physics is one allowed to say that the immutable laws of physics somehow changed as a way to blend the theories of the early universe after the big bang to the expanding universe we see today. The speed of light is a constant, oops, only from this point forward, same with the effects of gravity, motion and everything else.
If all of that is true, that the laws of physics, of nature, itself, can mysteriously change with no rhyme or reason, it's almost as if some external force were directing the formation of the universe. Oh, wait, that sounds too much like a deity, so that can't be correct. No, instead, we have to accept that somehow, everything around was was created in an instantaneous blink of an eye. Well everything, that is except physics. That was created separately some time later.
Or maybe, the physics didn't change, but math did. Maybe in the earliest universe it was permissible to divide by zero. I'm not sure who would have granted that permission, but if you are allowed to divide by zero, you can pretty much prove anything mathematically, so anything goes at the moment of the big bang! After all, dividing by zero just yields infinity and at the point of the big bang, the universe was an infinitesimally small place, so infinity was a lot smaller, too. So, like the speed of light, maybe infinity is relative, too, in which case it turtles all the way down (and up).
Eddies, in the space-time continuum.
Ah, is he? Is he?
You're a temporary arrangement of matter sliding towards oblivion in a cold, uncaring universe
the assumption that the current physical laws and constants were true then. By definition, they weren't - the four fundamental forces did not assert themselves until a finite period of time
If they didn't "assert themselves," does that imply that they did exist? I think that this way of speaking is a little confusing, because we believe that current "laws" represent special cases of more general laws, rather than different laws entirely.
If nothing had mass at the instant of the Big Bang, how does Einstein's theory of Relativity apply? Objects become infinitely massless as their speed approaches c?
Massless particles inherently move at c. They can't be accelerated or decelerated because they have no inertia, although they do have momentum.
As far as we know, this was just as true right after the big bang. Particles, or field excitations or whatever, had no mass, and moved at c. They did have energy, and an energy density, and therefore were gravitationally attracted. This attraction would be described by quantum gravity, instead of General Relativity.
Once the particles acquired mass via the Higgs mechanism (probably at or about the same time that the modern-day forces became completely separated), the universe was still an ultra-hot quark plasma, so the newly massive particles still moved very rapidly. Just not at c.
.: Semper Absurda