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Kepler Watches White Dwarf Warp Spacetime
astroengine writes "The Kepler space telescope's prime objective is to hunt for small worlds orbiting distant stars, but that doesn't mean it's not going to detect some extreme relativistic phenomena along the way. While monitoring a red dwarf star — designated KOI-256 — astronomers detected a dip in starlight in the Kepler data. But it wasn't caused by an exoplanet. After some careful detective work, the researchers found that the red dwarf was actually in orbit around a binary partner — a white dwarf. As the white dwarf passed in front of the red dwarf, the starlight was enhanced by microlensing — a phenomenon caused by an intense gravitational field focusing light from behind. This had the counter-intuitive result of causing the starlight to dim when the white dwarf passed behind the red dwarf and then brighten as the white dwarf passed in front. This is one of the first discoveries of a binary partner through microlensing. 'Only Kepler could detect this tiny, tiny effect,' said Doug Hudgins, Kepler program scientist at NASA Headquarters, Washington. 'But with this detection, we are witnessing Einstein's theory of general relativity at play in a far-flung star system.'"
Can this be used to make inferences about the laws of physics, constants, etc. as they are at that distance/time ago?
Since the current Kepler has produced stunning science, I sure hope they put another one up when this one conks out thanks to losing the last of its gyroscopes. It's a shame that Kepler is facing a crash just as it is hitting stride.
It's entirely true that faster than light travel is forbidden by general relativity. However, geometries with closed timelike curves, which can behave very much like time-machines, are not forbidden. It remains to be seen if such curves can be created and controlled. If they can, then a more complete model would be needed to include the effects of such phenomenon. As it stands, such curves could behave in several ways. In one formulation, self consistency would always be required. In another, such curves could be through another dimension, leading to self-inconsistent histories.
Most importantly, closed timelike curves are sufficiently rare that we have not observed natural occurrences. So, although such possibilites are interesting to consider, they are, ultimately, far beyond our current technologies.
till i realized it was white dwarf, not Red Dwarf...
Be seeing you...
Ye cannae change the laws o' physics
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Kepler should have stepped in and told the dwarf to stop.
OTOH "White Dwarf Warp Spacetime" sounds like something the Hulk would say, so perhaps a wise move to stand back and watch.
Maybe we can use imagination to move white dwarfs around to create dark matter bridges between the stars?
But, for example, the Alcubierre drive would allow us to travel to the stars in reasonable subjective time without FTL travel. If it could be built (manipulating multiple Jupiter-sized masses is currently a bit of a problem).
Consciousness is an illusion caused by an excess of self consciousness.
Not related to TFA per se, but from what I am understanding of exoplanet spotting is that it is predicated on a star and planet pair being observed being on an orbital plane of which Kepler can observe the edge. As otherwise how would the star light be seen to dim/brighten. Is this a fair statement? And if so does that mean that we are only capable (at the moment - I'm sure the future Lunar observatories will change things) of discovering exoplanets that lie on a plane whose edge points to Earth? And are the orbital planes of exoplanets parallel to our own solar system, or are they distributed all over the place?
I want to know for both the science, plus pretty well every science fiction book I have read has the protagonists entering planetary systems along the orbital plane (except for the sneaky bad guys who attack from above or below).
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LOL@SpaceTime
Physicists and creativity is bad combination.
No but there are 800 posts on reddit about how codeButcher is a complete tool already...
I can't help but notice that as our technology becomes more and more advanced, the narrative gets closer to and more interchangeable with sci-fi..
The starships prime objective is to hunt for small worlds orbiting distant stars, but that doesn't mean it's not going to detect some extreme relativistic phenomena along the way. While monitoring a red dwarf star — designated KOI-256 — the crew detected a dip in starlight in the Kepler data. But it wasn't caused by an exoplanet. After some careful detective work, flight astrophysicist Lt. Slarti B. Artfast reported that the red dwarf was actually in orbit around a binary partner — a white dwarf.
I swear, this is how I read 80% of the astronomical articles I come across.
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You sound like a typical creationist. Stop commenting, you're worse than Hitler.
However, geometries with closed timelike curves, which can behave very much like time-machines, are not forbidden.
WAT? CTC is relativist jargon for "time machine". They are exactly time machines. They violate the Weak Energy Condition, which means that they are indeed forbidden. They may occur at the smallest scales or below black hole horizons, but not at normal scales under normal conditions. If they did, they would tend to explode violently anyway (mechanism: self-focusing gravity wave beams along the closed timelike path).
The Alcubierre drive is a hypothetical faster than light drive based on general relativity.
If you want to go pretty much anywhere you want in a reasonable subjective time all you have to do is figure out how to accelerate at 1 g or so for a couple of decades. There are proposals for how to do that without needing Jupiter sized masses or negative energy. A ramjet comes to mind.
It is mostly the fine structure constant that is used to check if the laws of physics are the same at huge distances. Any change in this would change the relative positions of the absorption spectra of hydrogen, et al, and this fine structure constant contains planck's constant, electric charge and emissivity of free space (IIRC) that have no reason to change in such a way as to keep this fine structure constant the same if any or all of these values change.
And absorption spectra, even redshifted, keep the same relative positions based on the value of that constant.
To the limit of possible resolution, the laws of physics are the same back to at least a billion or so years after the big bang.
And the universe doesn't constitute a time machine by any meaning that would be given to the name.
I.e. we can travel forward in time at different rates in this universe, but we wouldn't call that time travel.
Kepler is a German name. You know who else had German names? Nazis, that's who!
There is a long list of unresolved problems with the Alcubierre drive, most of which seem to be ignored by pop-sci outside of the main issue of requiring a large mass of a exotic material not seen before (that multiple Jupiters of mass, or even the revised versions using less, is not just regular matter... but something we don't know if it even exists). There are other problems, such as the bubble being uncontrollable by the ship, so it would have to be constructed more like a railroad, or that within the bubble, there would be a massive amount of radiation generated if you tried to go faster than light.
Already 10 posts! And not one reference to US gun law! And only one reference to the Nazis.
FTFA :- "microlensing — a phenomenon caused by an intense gravitational field focusing light from behind. This had the counter-intuitive result of causing the starlight to dim when the white dwarf passed behind the red dwarf and then brighten as the white dwarf passed in front"
Not sure why this is counter-intuitive. The light would only appear brighter if you were observing from the focus of the microlens, or near it; elswhere it would dim, even on the same axis if you were far enough beyond it. So it just depends on the strength of the gravitation and your distance away, and the two dwarves are likely to have different gravitation.
hey violate the Weak Energy Condition, which means that they are indeed forbidden.
By the weak energy condition, but not necessarily by the laws of physics. Wormholes wouldn't be "normal conditions". Given that the weak energy condition is violated on quantum scales, as you already noted, that's one avenue by which you might be able to exploit the math.
I'm feeling a bit dim and I guess I need some help from one of the big-brains out there, please.
I understand the lense effect causing the red dwarf to brighten as the white dwarf passes in front of it, but why would the red dwarf dim as the white dwarf passes behind it? I read the article and it doesn't clarify - at one point it says the red dwarf would dim as the white dwarf passed behind, at another it said that when the white dwarf went behind the red dwarf there would simply be 'no starlight enhancement', indicating that it wasn't dimming, just that it wasn't being enhanced.
Am I being dim, or is the article slightly misleading on this one point?
Hmmmm....a white dwarf dancing with a red dwarf. That should infuriate the skinheads!
No the summary said "the star got brighter when something dark was in the way. that's pretty counter intuitive"
And it is if you're a normal person who doesn't immediately think of gravitational lensing when imagining a light source occulted by a dark body.
After doppler shifts and transists, gravitational lensing is the 3rd most used method to find planets.
grivitational lensing planet detection
And, therefore, substantially cooled. I am surprised that it wasn't detected directly like all the other white dwarfs we know about. (Like Sirus B)