Recent content by mjacobsca

You seem to be under the impression that the only way to test these theories is to probe the universe at the Planck Scale. That is one way to go about it, but certainly not the ONLY way. Theorists are working on ways to explain large scale structures based on these theories, and certainly...

LONG before people would feel any sort of "carnival-ride" forces, the Earth would experience tremendous tidal effects from the 3 solar mass black hole, causing ruptures in tectonic plates and mass devastation. One could envision Yosemite's super-volcanoe and other volcanoes erupting all at once...

Venus does have substantial atmospheric loss. But it's atmosphere is 90 times as dense as the Earth's, so it will take a long time for it to be completely stripped away. I don't think there is much active vulcanism adding more to it. Also, and this is worth mentioning, Venus' atmosphere has high...

Venus has no magnetic field, as you suggest, but 1) it is much larger than Mars, which allowed it to retain a very thick atmosphere comparatively, AND 2) it experienced an extreme amount of vulcanism which released tons of CO2 into the atmosphere in addition to whatever atmosphere was already...

IF evidence of life is found on Mars, and IF it shares similar bio-chemical properties, then the odds will be higher than what we can estimate today. For now, your idea falls in the realm of theoretically possible, and nothing more. Life could form anywhere and be blasted into space by asteroid...

Wouldn't it be easier to create a magnetic field on the surface? Possibly with some massive magnets? Either way, we are really good at generating electricity, so perhaps we can leverage this to induce enough magnetism to protect the planet. I think I read somewhere that the actual strength of...

If we add gravitons to the mix, do we still get warping space? I've always visualized the bed sheet pictures as a graphical representation of how gravitons work. But I'm not sure if they conflict with GR or not. If gravitons are in play, then maybe nothing has to warp at all?

I've seen models with 50-100 protoplanets being formed during planetary formation. Most of these collided or were torn apart from gravitational interactions with each other. Very few would be destroyed by the sun. Some would definitely escape orbit via gravitational interactions as well.

Scientists would know pretty early that a black hole were approaching. As suggested earlier, gravitational lensing would be significant from a measurement standpoint. I believe numerous pulsars are currently used for looking for gravitational waves (search for pulsar timing array). Space...

Near light speed velocities may not kill you. But an impact with a grain of space dust might. You would need an immense shield to stop debris from obliterating your vessel at those speeds. That seems as big, if not bigger, than the technical hurdles of accelerating to fantastic velocities.

Stu21, look into the Rare Earth Equation. It adds a ton of variables to the Drake equation. Whether you agree or disagree with its conclusion, it should give you more food for thought as to the rarity or lack thereof of the conditions needed for Earthlike conditions. It is by no means the...

You might be interested in the book "Death from the Skies", by Phil Plait. It covers various apocalyptic scenarios, and discusses the dangers and odds surrounding them. Read this, and supernovae may not be your biggest worry any more. :)

Is it possible that the value of Pi is related to the properties of the spatial dimensions of our universe? Could another universe with different properties see circles differently and arrive at a different value for Pi? After all, Pi is determined based on ratios determined within our own...

The Kepler mission has proved that planets are extremely common, and rocky planets probably are as well. The Rare Earth theory does not disagree with this. The Rare Earth Theory even says that life is probably common. However, it lists numerous variables that pose enormous challenges to complex...

This topic was discussed a bit last year. Here's the link: https://www.physicsforums.com/showthread.php?t=485500