Physicists Do What Einstein Thought Impossible 193
An anonymous reader writes "Einstein worked on Brownian motion (the movement of small particles in a fluid as they collide with the fluid's molecules) in 1905, but said it would be 'impossible' to determine the speed and direction of a single particle during this dance. Now researchers have gone and done it, by suspending a dust-sized glass sphere in air (which slowed down its dance moves, since it had fewer collisions with spaced-out air molecules than it would have had with water molecules). The researchers held the sphere in place with 'laser chopsticks,' and then watched how the glass bead bounced around to determine its direction and speed (abstract)."
To avoid confusion (Score:5, Insightful)
Keep in mind (Score:5, Insightful)
When people say "impossible" they generally mean "not possible given what I currently understand about XYZ"
Unless Einstein explicitly said "this will not be possible, ever"
I mean, heck the article demonstrates this itself:
"In 1907, Einstein likely did not foresee a time when dust-sized particles of glass could be trapped and suspended in air by dual laser beam “optical tweezers.”"
I'm sorry but: No freaking shit. In 1907 I doubt many people would have foreseen that
Bad Experiment or Bad Reporting (Score:3, Insightful)
Slightly Squiffy Reporting... (Score:5, Insightful)
Did they *really* prove they exactly measured it? (Score:5, Insightful)
If the glass bead were moving in such a way that was too subtle for them to measure, would they even know they couldn't measure it? What if Einstein was right and was simply implying that the movements eventually broke down so far that they were unobservable (similar to Planck's work)?
but... (Score:2, Insightful)
Re:Did they *really* prove they exactly measured i (Score:5, Insightful)
Dumb summary (Score:5, Insightful)
If you read the PhysicsWorld [physicsworld.com] article, you'll see it actually says:
But he believed that it would be impossible in practice to track this motion, given the incredibly short timescales over which the Brownian fluctuations take place
Ahhh... still don't have the original source quotation from Einstein here, but it sounds like Einstein believed it was "impossible in practice" - in other words, that the technology didn't exist at that time to measure rapid fluctuations over microsecond or even nanosecond time scales, and maybe he couldn't even imagine such technology existing.
So he never actually said he thought it was beyond the physical limits of the universe. There was no proof or physical law involved.
Now call me up when somebody figures out how to move matter or information faster than the speed of light (i.e. group velocity greater than c). Einstein really did believe that was *impossible*.
Re:To avoid confusion (Score:4, Insightful)
Re:Bad Experiment or Bad Reporting (Score:3, Insightful)
Because you can come up with a question that is not explicitly answered by the article does not necessarily imply either a bad experiment or bad reporting.
It means you probably want to read the paper.
Re:Infinite Improbability Drive (Score:5, Insightful)
So are you suggesting that the infinite probability drive is improbable? Maybe it can run off of it's own improbability.
Re:Keep in mind (Score:3, Insightful)
Re:Infinite Improbability Drive (Score:3, Insightful)
By design, all claims that the Improbability Drive doesn't actually work are false.
Claims that it doesn't work well are also false.
Nice try, though. Tea is the secret. They only MEASURED Brownian motion, no word on how they might either predict it, control it, or even duplicate it. But if they could in fact duplicate a Brownian circumstance, the Improbablity Drive stil works, because, well, despite the elegant engineering, it is improbably successful. Or something like that. Keep your towel handy.
Comment removed (Score:3, Insightful)
Re:Am I missng something? (Score:3, Insightful)
Re:Keep in mind (Score:3, Insightful)
When people say "impossible" they generally mean "not possible given what I currently understand about XYZ"
People don't understand the scientific method, and many don't want to. I had a discussion on slashdot yesterday about Galileo (brought on by the story about Copernicus) and someone had the simple mindedness to suggest that since Galileo didn't know that the orbits of bodies were elliptical rather than circular, that the Roman Catholic church was justified in their treatment of him and suppression of his ideas. A clearer demonstration of misunderstanding of the scientific method I could not have thought up.
Re:Impossible for his time (Score:3, Insightful)
It worked on you though, didn’t it? ;)
Currently Impossible (Score:3, Insightful)
Unless Einstein explicitly said "this will not be possible, ever"
He did not - as you suspect what he meant was that it was "not possible with current technology" and certainly not that it was impossible in the same vein as "it is not possible to travel faster than light". It would be like someone today saying that it is impossible to build a 500PB hard disk - what they clearly mean is that it is impossible AT THIS MOMENT IN TIME to build a 500PB disk not that it will never, ever be possible to do so.
Of course being a famous physicist the media have no qualms about hyping it as if somehow they have done something that contradicts Einstein because it attracts attention and cannot be proven to be wrong even it is extremely clear what he really meant.
Re:This Einstein Fella is a Hack (Score:2, Insightful)
Yeah, and when was the last time he published anything? I doubt he'll make tenure at this rate.
Dude, wait. Isn't Einstein, like, dead?
Isn't that one of the major prerequisites for tenure?
Re:Keep in mind (Score:3, Insightful)
Also, he was a pretty big dick to everyone.
Then punish the man. Do not suppress what he had to say.
The fact that his evidence was extremely difficult to duplicate, and contained major flaws, were also strikes against him. For example, he was completely wrong about comets.
There is nothing in the scientific method that says a scientist should be ignored unless his or her work contains absolutely no flaws. There's certainly nothing that says the work should be suppressed or that he should be tortured, denied medical treatment and imprisoned.
Furthermore a lot of his work was trivial to duplicate. For example showing the crescent shape of venus, or the moons of Jupiter required only that a telescope be aimed at them.