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How Would an Astronaut Falling Into a Black Hole Die?
ananyo writes "According to the accepted account, an astronaut falling into a black hole would be ripped apart, and his remnants crushed as they plunged into the black hole's infinitely dense core. Calculations by Joseph Polchinski, a string theorist at the Kavli Institute for Theoretical Physics in Santa Barbara, California, though, point to a different end: quantum effects turn the event horizon into a seething maelstrom of particles and anyone who fell in would hit a wall of fire and be burned to a crisp in an instant. There's one problem with the firewall theory. If Polchinski is right, then either general relativity or quantum mechanics is wrong and his work has triggered a mini-crisis in theoretical physics."
Heck, considering what we know about the environments around black holes, not only will the gravitational tides kill you before you reach the event horizon, so will the radiation.
Everybody repeat after me: "Black holes ain't yer friend. Don't try to hug them, you will die."
They've found numerous stellar objects of various sizes that conform to the preditions of black holes. (Mass, diameter, etc) Though none have been directly observed, their 'feeding' does generate a lot of energy that is detected when something falls in. Just recently one that had been relatively quiet for some time gave of a nice 'burp' of radiation as it apparently 'ate' a planet.
:D
Have we been to a black hole? No.
Have we taken photos of an actual black hole? No.
Have we seen gravitational effects that look exactly like what a black hole should have? Yes.
Do those gravitational effects calculate out as something of several to millions of solar masses in a tiny volume that can't exist in any non-black hole way that we are aware of? Yes.
Have we seen the radiation from an accretion disk falling into and being destroyed by a black hole as predicted? Yes.
Is a black hole what astrophysicists think it is? Probably.
Is a black hole what non-scientists (hollywood, general public, dentists, etc) think it is? Probably not.
Do you really exist? This is about black holes, but your existence is only a bit less theoretical than that of a black holes, though some of the specifics of either may not be what is generally thought about them.
And no, a black hole is not god dividing by zero. It's more likely an alien mad scientist multiplying by the square root of negative zero.
Assuming you're not trolling, that's a nice story, but that's not how science works.
The trouble is that "what we know about black holes" is all theoretical and mathematical.
Usually, the first step in science is to observe something. In the case of black holes, our knowledge of their existence can be traced back to a few experiments, which provided pretty solid evidence against the prevailing theories of aether. The observation that doesn't match the expectation means that the theories aren't right, and must be changed.
In fact, many of today's experiments are simply re-running old trials, but with more precise technology. Rather than dropping rocks off a tower, we can measure how fast individual atoms fall, giving us a more exact understanding of gravity. Usually the results are a perfect match for what's expected, but sometimes they aren't.
Black holes were invented to explain present-day theories about the motion of stars and galaxies.
Next comes the theory. Starting from the results of those experiments, Einstein hypothesized his theories of relativity, which are really little more than a collection of relationships derived from the assumption that the speed of light in a vacuum is constant. His theories explained the results of previous experiments, and importantly, provided a set of formulas that can be used to make predictions for future experiments.
Mathematics are very useful in describing measured experiments and observations in the physical universe. As soon as mathematics and computer simulations go beyond what is actually observed and measured, it no longer describes the real world were living in.
The relationships in the physical world are described with mathematics. Sometimes, when math is insufficient to easily describe a particular relationship, new mathematical forms are invented to accommodate the real world. Ultimately, though, every physicist knows that the mathematical models do not prescribe reality, but describe our understanding of it. Again, we use those models to predict the outcome of future experiments.
At the center of these hypothetical, theoretical black holes is this mathematical entity that has been called a "singularity". This is another mathematical fiction that can't exist in the known universe.
That depends on the rules of the known universe. in 1915, Karl Schwarzchild transformed Einstein's theories of relativity into a form that would require black holes. This means that Einstein's formulas can only be correct if the universe allows black holes. If the universe does not allow black holes, then Einsteins formulas must be wrong - though less wrong than the aether theory they replaced.
Perhaps it is time to examine some of these widely held theories that require these mathematical fictions.
That's what experiments are for.
No one has ever directly observed a black hole and thereby shown that these things even exist in the real world.
Black holes have been observed many times.
In 1929 an astronomer named Edwin Hubble discovered that "red shift" of distant galaxies. Then he made the assumption (belief, faith) about the cau
You do not have a moral or legal right to do absolutely anything you want.