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Physics, Astronomy & Cosmology / Why does string theory (M theory) require extra dimensions.

« on: 24/06/2020 05:19:38 »

The depictions always show the strings vibrating  and floating in a space resembling the dimensions we commonly see, but the experts tell us that the theory requires several extra dimensions to operate coherently. They never tell us why.
Can someone provide a brief description of why standard dimensions are inadequate, and what the extra dimensions provide?
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Physics, Astronomy & Cosmology / Are we doing enough to get by?

« on: 05/05/2020 16:40:55 »

Enough to get by the next mass extinction? We don't seem to have any sense of urgency. The fact that we can't predict the date makes the next mass extinction no less inevitable. There have been (at least) five mass extinctions on the planet before. We are the only species that ever lived that is capable of foreseeing their own extinction...and possibly averting it.
The planet was formed and evolved in incredible and unfathomable violence. The Early Bombardment period responsible for the wall-to-wall cratering on the moon has largely subsided. This was equally true when the dinosaurs had a bad day. And the skies almost daily provide us with more surprises.
At a more local level, the entire Yellowstone Valley is the huge caldera of a super-volcano, and it's due to blow again anytime. Add extreme atmospheric changes to the dangers. Venus didn't require any man-made boost to render it uninhabitable. These are but a few of the possible extinction events we know about.
Should we heed the advice of the world-famous cosmologist and scientist, Moe Howard, who admonished his colleagues, Larry and Curly, "Spread Out!"?
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Physics, Astronomy & Cosmology / What do you know about supernovae?

« on: 10/04/2020 18:29:21 »

We are told supernovae are the only places that contain the pressures and temperatures necessary for creation of the heavier elements. Let's go with that.
Given the infrequent incidence of supernovae and their brief duration in that state, a logical conclusion is they have to make lots of heavy elements really fast. Apparently far faster than they created the lighter elements as a massive star. (Supernovae HAVE also been happening for a long time.) Do the numbers work for what we observe in element ratios?
The next question involves distribution of the heavier elements. They are ejected in an expanding spherical shell at velocities that exceed the escape velocities of surrounding planets and stars. What slows them enough to go into orbit around anything? Other than a direct hit or something very close, it would seem to be a very privileged place where heavier elements have found a home. But we don't have any trouble finding them.  How's that work?
The last question involves the shock wave from a supernova as it encounters a dust/hydrogen cloud. In my thought experiment, the cloud can be condensed, left the same, or further dispersed. Cosmologists almost always pick condensed, "triggering" collapse into new stars, while providing little evidence or argument for that pick. Sounds like a rainmaker with a cannon...he believes, so should you! What do you think?
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Physics, Astronomy & Cosmology / Is the Big Bang Theory Hokum?

« on: 02/03/2020 14:50:16 »

"Extraordinary claims require extraordinary evidence." Carl Sagan

Some cosmologists suggest the Big Bang theory has too many holes and patches to remain viable.

When the numbers didn't work, Alan Guth simply plugged in a conjured arbitrary "inflationary period" to fix the numbers...no reason for its' start, its' length, or its' termination...just fixed the numbers...

The "something from nothing" argument relies on extrapolation from a quantum fluctuation at an atomic level to an entire universe popping out of nothing....we don't observe universes popping into existence from nothing...

Cosmic background radiation: Our instruments are absolutely exquisite, capable of counting individual photons. What we are seldom told is that the TOTAL cosmic background radiation measured has the energy of a couple dozen snowflakes crashing to earth--not adequate or compelling, much less extraordinary, evidence for the extraordinary claims of a universe.

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Marine Science / How do whales have time to inhale?

« on: 25/02/2020 15:01:05 »

We're all familiar with the multi-second "Thar she blows" exhalation of whales.
But ALL the videos seem to show only a fraction of a second after that before the blowhole is submerged. It doesn't appear that they've had time to take in enough fresh air to replace the air they expelled. Obviously, it works. How?
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Plant Sciences, Zoology & Evolution / Do hummingbirds fly across the Gulf of Mexico?

« on: 17/02/2020 15:30:05 »

They "bulk up" prior to migration. Nonetheless, for a bird that normally must feed every 15-20 minutes, a 25 hour flight seems unlikely. Also, this is the only time that they are purported to fly at night.
What would drive a tiny bird to launch itself over the Gulf with no land in sight? They don't migrate in flocks, and for the birds just hatched in U.S., it's a first time solo experience.
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Physics, Astronomy & Cosmology / What is the explanation for non-locality?

« on: 17/02/2020 13:46:28 »

Spooky action at a distance or quantum entanglement are examples.
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Physics, Astronomy & Cosmology / Does gravity have a longitudinal influence on light?

« on: 11/02/2020 16:08:39 »

Gravitational lensing has demonstrated gravity's lateral effect on light (Yay, Einstein!). It would seem to follow that there is also a longitudinal influence. Gravity obviously can't make light go faster, and I haven't seen a discussion of slowing it down. What about a frequency influence? "Red shift"?

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Physics, Astronomy & Cosmology / Did Einstein "kick the can" on gravity?

« on: 10/02/2020 16:51:27 »

Einstein could discover no mechanism for gravity's influence across space...
So he theorized that matter warps space...and provided no mechanism whereby matter does this.
I don't see this as a good answer.

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Physics, Astronomy & Cosmology / What's wrong with the gravity analogy?

« on: 09/02/2020 15:37:54 »

A bowling ball on a rubber sheet to illustrate how "warped space" makes orbits work is OK as far as it goes.
What if the two bodies have no relative motion? They are sitting there occupying each other's curved space, but neither is moving thru that curved space. Is there no gravity?