27710 say that we have "something" in a area with little to no energy except for the "something", if the "something" was moving around we would see it going faster than it would in an area with lots of energy (like earth's atmosphere) because all that energy is distort...

tAtVgHvt05M A new method of measuring the universe's early expansion history by the UV and X-ray emission of quasars has led to the startling result that the strength of dark energy appears to have increased over time.  Does this mean the Lambda-CDM model with dark energy as an unchanging cosmologi...

Was just going to post that.   Very interesting, and awesome that it was captured by 2 satellites!

27696 I meant proper time, both would be good to know, but I would want to know how time is in the "spacetime distorter's" frame of reference, which I believe would be proper time. What we can change is the relationship between proper time and coordinate time.  But this is just what time ...

27680 What's the annual precipitation in this area? Average annual precipitation here is around 300cm, most of which falls during the wet season as snow from October through April.  Average annual snowfall at the ski resort is 16.3 meters, and the resort also holds the official world record for mos...

27688 I was wondering if a person somehow managed to go 13.7 billion light-years from the center of the universe would he be able to see Big Bang itself (with a Hubble). We can see the Big Bang (or at least very close to it: within about 380,000 years of it, before which the universe was opaque) by...

27682 This still doesn't answer what I asked, I said, "if you could SPEED UP TIME", not "if you could go as fast as light". I answered right here . (Post #1455).  The problem with the question is that it's unclear what "speeding up time" means.  Coordinate time, or pro...

Photos from a trip in the alpine back country.  It was hot .  Clear, windless, and +10C with the sun beating down, I almost wanted to shed every layer of clothing and lay in the snow with a nice tropical drink. With the heat came wet avalanches, so awareness of the terrain and changing snowpack cond...

What Matt in the PBS Space Time video means by "reversing the direction of your changing spacetime interval" is to change the sign of Δs 2 .  For allowed (slower than light) motions, Δs 2  is negative, while for faster than light motion, it is positive.  Their diagram represents the negati...

27635 if you could somehow make time go faster, how would that look on the diagram? There's a subtle difficulty with this question.  What do we mean by "making time go faster"?  Time can refer to two different things:   coordinate time and proper time .   Coordinate time is what we mark a...

Stellarator wrote:

Qr Bbpost If it doesn't make any sense, just keep re-watching it 'till it does.

And ask questions, of course. 

Propulsion Disk , the image was an animated gif, so perhaps that was the problem.  I replaced with two static images, see if it shows up for you now. 27618 But anyway, so mass BENDS spacetime and doesn't stretch or shrink it, is that what the "relativity of simultaneity" is? Not quite.  T...

Propulsion Disk , very interesting questions, and y ou're on nearly the right track thinking about them. :) In simple terms, mass "bends" spacetime, in the sense of making it curved (but in a four-dimensional way which is difficult to visualize, though made precise in the math of general ...

27492 PETM occured relatively recent in Earth's history, so much of the crust still exists today.  Also, would such an event have been recorded if it happened during a snowball or waterworld period? I of course make no claims that the geologic record is a complete record of all of Earth history.  H...

As a test of memory during my teenage years I learned pi to 100 digits, but since then it has fallen down to 50.  Maybe the amount of pi I retain decreases in proportion to my remaining life expectancy?

3.14159265358979323846264338327950288419716939937510...