Slashdot Mirror
NASA Poised To Topple a Planet-Finding Barrier (nextbigfuture.com)
schwit1 shares a report from NextBigFuture.com: Babak Saif and Lee Feinberg at NASA's Goddard Space Flight Center in Greenbelt, Maryland, have shown for the first time that they can dynamically detect subatomic- or picometer-sized distortions -- changes that are far smaller than an atom -- across a five-foot segmented telescope mirror and its support structure. Collaborating with Perry Greenfield at the Space Telescope Science Institute in Baltimore, the team now plans to use a next-generation tool and thermal test chamber to further refine their measurements. The measurement feat is good news to scientists studying future missions for finding and characterizing extrasolar Earth-like planets that potentially could support life. To find life, these observatories would have to gather and focus enough light to distinguish the planet's light from that of its much brighter parent star and then be able to dissect that light to discern different atmospheric chemical signatures, such as oxygen and methane. This would require a super-stable observatory whose optical components move or distort no more than 12 picometers, a measurement that is about one-tenth the size of a hydrogen atom.
I guess you haven't heard of the James Webb Space Telescope (JWST).
Now launching in 2019 unfortunately. :-/
If intelligent life 15 light years away can give us schematics for FTL drives, we could go there within a lifetime
There are maybe 100 stars within a 15 light year radius, and the chance that any of them happen to have intelligent life right at this moment is very slim.
>to find planets we'll never be able to reach!
It is entirely possible there are 'habitable' planets within reach of our technology - if we're willing to invest in building a heavily redundant generation ship and live forever in domes when we arrive at the destination, totally dependent on advanced technology for survival.
If I were a gambler, I'd say finding a Mars-equivalent would be like hitting the jackpot...
You've basically described the James Web Telescope, it has 18 such mirrors. It's IR, but that is optical for cosmological distances.
Let's say there are exactly 100 stars within a 15 light year radius. Going by the process of elimination, we already know there's only 99 of those stars which could contain intelligent life around them.
#DeleteFacebook
You never heard of atmosphere processors? It's a one terawatt fusion reactor power plant, about 1500 metres in height, manufactured by Weyland Corp.
#DeleteFacebook
yet the train is going at 1.2 light speed when measured against the outer ring.
No, it's going 0.88235 light speed when measured against the outer ring, because you have to apply the Lorentz transformation when adding relativistic speeds. The relative velocity of any two objects can never exceed the speed of light no matter how clever you set it up.
Yeah, and then they went and discovered that pesky neutron. Oh, and quantum mechanics. And don't forget, quantum field theory, an absolute plethora of particles, neutrinos, and both special and general relativity! But even before these developments drove a stake firmly through the heart of "gravity as electromagnetism in disguise", as you note:
Attempts to unify the two basic forces of the universe, usually by reducing gravitation to electromagnetism, was part of the electromagnetic program, but in spite of much work, no satisfactory solution was found.
Now, of course, just because they didn't find a satisfactory solution doesn't mean that there isn't one. However, in the meantime, solutions that ARE satisfactory have been obtained that describe gravitation as an interaction that is very much not reducible to E&M, or as curvature of space-time by mass-energy that need not be (and in the literal bulk of cases, the quark-quark interactions that govern nucleons and nuclear binding energies, is not) electrodynamic in origin. While I agree that to a large extent particle "mass" is the self-energy of its local field structure and might end up ALL being field energy in the end (once we unify field theory properly and completely), there are more fields than just gravitation and electromagnetism and more elementary particles than just electrons and "nuclei", which is about all that was known in 1904. Also, Maxwell's Equations simply don't have any ROOM for gravitation, with or without magnetic charges (symmetric completion). Whatever the TOE turns out to be, it (almost certainly) isn't "just" going to be MEs classical or quantum or QED tied to ELECTRONS. You see, sir, there are those pesky definitely-not-an-electron neutron, neutrino, muon, quark, photon, gluon, heavy vector boson thingies, many of which we can directly "see" in modern collider experiments, others which we can almost directly infer (quarks BOTH from structure AND from observations of jets).
And then there is the Higgs particle, which has possibly maybe mostly been seen but which awaits a few more sigma and which (sigh) sure, might turn out to be a chimera once again. But it is a pretty compelling theory and it, not MEs, does appear to provide an explanation for mass.
Perpetuation of an old idea in the teeth of all of the evidence accrued in the meantime that it was incorrect requires a sort of wilful blindness and is indeed the sign of either a crackpot or a troll. OR you could just be kidding on the trollish side of things, but reposting an old thing from well over 100 years ago... really?
Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
China has astronomically qualified sites on the Tibetan Plateau at over 17,000 ft (5200 m) and is already a partner in the Thirty Meter Telescope project. Rather than waiting for the American legal gears to grind away into eternity, site it there and get it built. Because its southern hemisphere companion instrument is already under construction in Chile, the long-baseline possibilities are unparalleled.
To make multiple telescopes work together "working as one large one", you have to control the positions of their mirrors relative to each other to a small fraction of a wavelength. That's what this is about.
I'm not sure what they need picometer accuracy for, though. That seems more than the requirement.
http://www.geoffreylandis.com
I would like an explanation of how we can talk of 1/10 diameter of a hydrogen atom. I have read similar dimensions in talk of how far the mirrors in LIGO wiggle. Less than the smallest atom, so, using STUFF how do you measure things smaller than, than, stuff? I presume it is an average of all atoms in the mirror, but still
One straightforwardly physical way to explain gravity is as a distortion of electron orbitals
Nope. Simple though experiment:
All EM fields are constrained to curved of space time. A side effect of this is that none of these fields may cross the event horizon of a black hole from the inside. No fields or particles inside can get out. Except gravity. Because how else would a black hole work? If gravity were some manifestation of electromagnetism, then the matter inside the black hole (from a collapsed start, for example) would not be able to influence matter on the outside. And this is clearly not the case, as evidence for the existence of black holes is their gravitational effect on external objects.
Have gnu, will travel.
Well, or...
You could consider existing science as the solution to a complex optimization problem in a very large dimensionality, where what you are trying to optimize is the probability that your whole interconnected network of beliefs is correct.
In which case, while I absolutely agree that one should remain skeptical of the existing set of best beliefs, and while there is no doubt that there have in the past and no doubt will be in the future major rearrangements or even paradigm shifts, there remains the simple fact that a) new ideas (like relativity and quantum mechanics) tend to embrace their predecessors and preserve their functionality in the appropriate domain; and b) THEY ARE EVIDENCE BASED. In the end, advancing hypotheses that have been soundly rejected by oh, a century's worth of work is just plain crazy.
This is for very good reason. In order to be credible, a "new" theory has to completely embrace everything that the old theory gets right AND get some new stuff right. Things like neutrons, neutrinos, atomic structure, nuclear structure, the actual particles observed to be created by nuclear collisions, and ever so much more.
In the meantime, maybe you should try to understand things like Gauss's Law and 1/r^2 force laws (and their underlying geometry) vs atoms "resonating together" sort of like the completely quantum mechanical DIPOLE INDUCED DIPOLE interaction seen in the SHORT range Van der Waals force. Until you do, it is difficult for me to even begin to explain why your assertion is absurd, and the "documentary evidence" supporting it, all from right BEFORE the major paradigm shifts that generated modern physics as we now best understand it, is utterly irrelevant and incorrect.
I also have no idea what "dead end" you are referring to in cosmology, and what your evidence is for considering the observations coupling gravitation to mass, which date back to Galileo, and the even stronger evidence coupling electrodynamics to not mass but charge, to be fundamentally incorrect. Note that I'm not addressing the difficulty reconciling general relativity, newtonian gravity, and quantum mechanics, because your remarks above seem to have nothing whatsoever to do with that, and because your proposed solution isn't even an ACTUAL proposed solution. That would require the support of a hell of a lot of real math and the demonstration that the new theory embraces the old and has actual quantitative explanatory power as well as direct evidentiary support, none of which exist.
Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.