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Lead on Lead Action, Justin Rants About Gravity, New Neutrino News, Wandering Mind, Fearful Brains, Skin Blood, Fastest EColi in the West, Your Mom Was an Alien Zombie, Uses for Electrocution, Gamma Bubbles, Brains on Yoga, Deformed Birds, and Much More!
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This evening I had the displeasure of hearing Justin screaming that the LIGO experiment is obviated by stellar observations of Galaxy collisions.
The reason Justin is wrong is that gravitational interference happens on the scale of the gravitational wavelength.
Ocean wave interference happens on the scale of ocean waves: you can see the rip tide form where two waves merge together.
Quantum interference is visible only at the tiny distances of the quantum world: double slits must be tiny to produce quantum interference.
Gravitational waves, if they exist, could be deteced by the laser interferometer experiment LIGO.
A galaxy collision, while an awesome event, is not an interferometer.
There is zero predicted interference pattern for a galaxy collision.
The reason for this prediction is that, on astronomical scales, stars act like point particles as they interact gravitationally.
Billiard balls are far too giant for quantum interference to be observed.
The same is true for the stars in galaxy collisions.
As for Justin’s ignorant procolimation that there is “no evidence for the existance of the graviton”:
You accept the existence of gravitational waves, right?
There is evidence for gravitational waves, like the Hulse-Taylor binary star system.
Gravitational waves are also a consequence of General Relativity!
Well, “graviton” is the word we use to describe coherent states in a gravitational wave.
If you accept the existence of gravitational waves, you must accept the existence of the graviton.
This is true for the same reason you must accept the existence of photon if you accept the existence of light waves.
If you accept the existence of sound waves, you accept the existence of harmonic notes.
Etc.
http://en.wikipedia.org/wiki/Hulse-Taylor_binary
http://en.wikipedia.org/wiki/General_relativity
http://en.wikipedia.org/wiki/Coherent_state
http://en.wikipedia.org/wiki/Wave–particle_duality
I usually love TWIS but the rant about gravity in this episode was really horrible. As with other of all the “weirdo physics things” it is the idea that best fits the data we have available atm. Obviously if data is gathered that contradicts it or makes someone go “aah wait, I have this other better idea” that can then be tested to see if it predicts things etc. then obviously there will be a shift in what is the generally accepted theory, that is how science works if you had somehow forgotten that? What it doesn’t do is jump every time someone screams “OMG There is all this weirdo stuff and its like soooooo weird and i like sooooo don’t get it so lets totally drop this idea and get some new cool stuff going!11one!1”
I can guarantee that my annoyance is only due to the show usually being very very good and entertaining, this was just a disappointing episode with regard to the inane rant.
Okay, I have been listening for a while and think I will get in the action commenting here. Specifically, I would like to comment on Justin’s rant on gravity waves.
Justin, you need to look at what LIGO is designed to detect. You seem to think the failure to detect gravitational waves from the Bullet Cluster indicates they don’t exist and LIGO should be shut down. However, LIGO was designed to detect gravity waves from nearby (several tens of millions light year distant) events such as merger neurton stars, not several billion light year distant events like the bullet cluster. Gravity waves attenuate with distance…I doubt we’ll detect much of anything from several billion light years away with LIGO!
However, it’s even worse than that. Galaxy collisions take place over millions of years resulting in small (relativistically speaking) accelerations which would result in gravity waves well below LIGO’s sensitivities (not even counting the extreme distance).
Finally, LIGO is designed to detect relatively high frequency (short wavelength) gravity waves. Any gravity wave generated by galaxy collisions would be extremely long wavelength, again, well outside LIGO’s range.
In short, if we had detected something from the Bullet Cluster, there would be a LOT of ‘splainin to do!
I feel your pain, A. Steen and hale-bopp. You know what interesting physics book I just picked up? Once Before Time by Martin Bojowald. It’s about Loop Quantum Gravity. Weirdo stuff *and* “aah wait, I have this other better idea”, both at the same time! Well, maybe, I haven’t finished it yet. 😉
Thanks for the comments!
To clarify, I don’t think that LIGO should have detected the Bullet cluster. I think that there should have been a ripple effect in the gravitational lensing of such a collision to support a gravity wave theory. This may be totally incorrect, but if we are seeking small effects in a local static system, a larger non static system such as the bullet cluster should show some sign of this on the larger scale.
Science does not know what Gravity is… that we have a word for it is just a place holder that describes several types of observations around a theme, but lacks actual knowledge of what we mean by it.
Very important in any discussion about gravity is to understand how we know what we do know about it. Everything we know comes from back engineering our observations. All of Newtons understanding was terrestrial. It works perfectly for launching rockets to the moon, but fails to explain much beyond our local area. Einstein found ways to predict the motion of Mercury, not by developing a theory in isolation, but by knowing the anomaly of its orbit and back tracking a way to fit it into theory. That we can predict something through mathematics is a fantastic feat of mechanical understanding, and when we understand how one piece of the puzzle works it allows us to make predictions about how others will work as well, to great success… but it does not mean we understand why it works that way. All the “why” it works the way it does concepts are not actual answers, but potential answers that require investigation.
Gendou – I love the double slit test, to me it shows evidence that space can be warped at sub millimeter levels without the introduction of mass… that space itself is a matter of freedoms of motion. Interesting side note to this, rainbows only occur in sub millimeter droplets of water… don’t understand the correlation precisely, but love that double slit and rainbows have something in common.
I stand firmly by my assertion that there is no evidence for the Graviton. I find the entire concept of the Graviton about as believable as an episode of ghost hunters, absolute paranormal gobbled-gook.
Hale-bopp – love the name… I met a guy named Chuck at Area 51 who spent most of his days taking photo’s of pilots testing aircraft over the Nevada desert, but who had better photos of the Hale-Bopp comet than I have ever seen published anywhere…
The LIGO isn’t designed to detect anything but passing trucks… they attempted to design it to detect
Gravity waves, found nothing, and decided it was the fault of the instrumentations sensitivity, not in the underlying theory… It will get a second shot in Advanced LIGO and I will still be betting as I have all along that it will find nothing.
I do not believe we are ever going to find a force, wave, particle or field that is Gravity. That we can describe it as such in certain situations does not make it so. What I believe we will ultimately discover is that what we call gravity is a property of space, a freedom of motions on a quantum level that however forceful it appears in our multi magnitudes of macro space… comes down to very tiny differences in probability of motion at the quantum level.
A.Steen – I don’t know if I disagree with you or totally agree with you… hmmm. I guess the way I’m seeing things is that whenever an observation comes along that should challenge current theory or “seems totally weirdo” it is made tame by forcing it, no matter how bluntly, to conform to existing theory. Where are the brave minds that are not afraid of questioning authority? Where is our generations Giordano Bruno, Galileo, Newton, Einstein, Niels Bohr, Susskind, or…
Oh, there he is… Erik Verlinde… the most reasonable person in the world.
http://pirsa.org/10050022/
OK, Justin. Slow down and think. We don’t just throw out the scientific method if we don’t like what we see. I hope you are playing Devil’s advocate here. Observe, hypothesize, design, test. I think 100 years is not a long time.
“I want answers now, Kirsten!” We need to recognize that our experience of the universe is flawed. The only way to glean any real useful model is to turn away from our senses and systematically and rigorously test.
Listeners, please teach a kid about the scientific method. Once that light bulb clicks on, and you realize you can’t trust your senses or your experience alone, the system of Democratic government works. Until then, we are free to be misled by those who talk the loudest.
Just listening to intro to 18th nov show, and justin claiming he doesn’t thing. Coal fired power stations are as efficient as a petrol engine.
I think you’re missing an important point. Petrol doesn’t come out of the ground ready to pump into your car. Do you have any idea how much electricity it takes to turn crude oil into refined petrol?
Last figure i heard (via robert llewelyn) was 17KWh per gallon.
That’s ignoring distribution cost, storage, power to run gas pumps etc etc.
Even without that i find it hard to believe that lots of small engines could be as efficient as one large power station. Pure economy of scale & heat recapture tech would seem obvously more efficient.
Justin, although we do not have direct evidence of gravitational waves yet, the Hulse-Taylor binary pulsar has two components that are slowly spiraling in toward each other at a rate that matches what we would expect if the were radiating gravity waves. I know this is not proof that gravity waves exist, but it is evidence that something is going on that matches a prediction. Any competing theory would have to be able to explain observations such as this and make predictions which differ from General Relativity’s gravitational waves that can be put to the test at some point in the future (knowing that we might have to wait for technology to catch up to do the experiment of course!)
“The LIGO isn’t designed to detect anything but passing trucks…” or people shooting at the tunnels as has been reported at the Livingston facility!
Hale-Bopp is my online presence and the name of a black and white cat I adopted in 1996 who has quite the attitude!
Fordskydog – i haven’t abandoned science in any way… I want science to pursue this. But if we have started with an assumption, tested that assumption and found no evidence that it is correct… test for alternatives.
Danielwould – Yes yes, not to mention the political cost of oil. I was doubting that a modern vehicle has worse emissions than a coal fired power plant. And you make some great points about the larger footprint of oil. On the coal side i’d add that only half the elecrticity produced makes it to the plug… the rest is lost in the transmision. So if the goal is emission reduction via electric vehicles, I still think the carbon cost of an efficient gasoline vehicle will be lower.
Justin, keep your god damn pseudoscience to yourself and let Kirstin talk. Seriously. Arguing with you is just as awful as arguing with a religious fundamentalist. You obviously have no interest in rational discourse. So just shut up.
“Science does not know what Gravity is” — NO! WRONG! *YOU* are the jerk who doesn’t know what gravity is! You clearly don’t understand the first thing about the scientific method. In physics, and science in general, a theory describes HOW something works, HOW to predict the outcome of experiment, and HOW to calculate the outcome. Physics, and science in general does NOT tell you WHAT gravity is, WHAT gravity means, WHY gravity exists, or WHY gravity acts the way it does.
http://www.youtube.com/watch?v=wMFPe-DwULM
Newton’s theory of gravitation is a theory of gravity that works on classical energies.
Einstein’s theory of relativity is a theory of spacetime that works at most energies.
A future theory will describe gravity even better, and will hopefully work all the time.
Saying that “Science does not know what Gravity is” is anti-science.
Saying that “General Relativity cannot correctly describe the big bang singularity” is a reasonable thing to say.
Here’s your fucking problem, man: YOU DON’T SAY REASONABLE THINGS!!!
Everything out of your mouth is hyperbole, dissent, or a lame joke at the expense of a serious conversation.
I have great interest in rational discourse…
Why is it required to be your rationality that I use in doing so?
And if I did adopt your thinking alone, what would we have to converse about?
as to the pseudoscience of my irrational discourse…
http://www.sciencedaily.com/releases/2008/01/080131094056.htm
the throw away line in this article link is where my argument is…
“However, the Universe might be absent of dark-matter particles at all. The findings of Dr Zhao are also compatible with an interpretation of the dark component as a modification of the law of gravity rather than particles or energy.”
That I’ve been saying this longer than its been a theory is pure intuition, critical thinking and speculation on my part…
but there it is – compatable… hm.