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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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Plant Sciences, Zoology & Evolution / Re: Do hummingbirds fly across the Gulf of Mexico?

« on: 06/05/2020 03:31:24 »

Even hurricanes for hummingbirds are not a hindrance.

Sounds particularly frivolous, since the maximum speed attained by a hummingbird in a dive is not equal to the windspeed of a minimum hurricane.

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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 / Re: Do you think we should attempt contact with aliens?

« on: 22/04/2020 15:49:04 »

Advanced civilizations destroy more primitive ones....that's the human history...
Hopefully we encounter slightly more civilized beings.

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Physics, Astronomy & Cosmology / Re: Do you think we should attempt contact with aliens?

« on: 18/04/2020 15:59:24 »

We are currently struggling to use quantum entanglement to communicate instantaneously, i.e. faster than c.
One theory is that even a slightly more advanced civilization will have long since abandoned using the electromagnetic spectrum for communication, and our current search is essentially "scratching where it don't itch."
.
A more fun theory is that we were "planted" on the garden of earth, and our broadcasts simply indicate we are "flowering" and will soon be ripe enough to eat....

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Physics, Astronomy & Cosmology / Re: Do You Think There Are Planets Around Alpha Centauri?

« on: 16/04/2020 15:27:07 »

Exoplanets are not really in doubt...everything we know suggests they are inevitable...
I am nonetheless highly skeptical of our methodologies of discovery.
Here's my question: Would an observer from a distant star system correctly "discover" our eight planets, and correctly predict their orbits and composition, using our equipment and methods? I remain unpersuaded.

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Physiology & Medicine / Re: Are differences in height the result of differences in access to food?

« on: 14/04/2020 16:06:09 »

All the 1000 lb. + marlin in the oceans are female. The males seldom exceed 400 lbs.

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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 / Re: How much would a freefall weight need to weigh to generate 55psi

« on: 09/04/2020 18:46:50 »

Syhprum, I didn't come here to be insulted, came here to ask a question.
                           
                        
                        
                           
                           
                           
                              

Read some other threads....ya come to the wrong place...

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Physics, Astronomy & Cosmology / Re: Wave-particle duality theory and the observable universe.

« on: 07/04/2020 15:05:04 »

Can the outcomes of wave-particle duality experiments be reflected in the world I observe and experience around me?

The earliest two-slit experiment exhibits quite clearly the duality.

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

« on: 25/03/2020 15:55:13 »

A non-Euclidian geometry has been posited to describe how parallel lines converge in curved spacetime. This is one explanation for gravity between bodies with no relative motion. Can parallel lines not also diverge in this non-Euclidian geometry? Why would we not observe repulsive gravity?

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Plant Sciences, Zoology & Evolution / Re: Do hummingbirds fly across the Gulf of Mexico?

« on: 23/03/2020 18:01:54 »

The birds normally go into a state of torpor each night, when their body temperature and heartrate drop precipitously. They are unable to fly in this state. The birds are unable to sustain their normal high metabolism and temperature overnight. Some experts have claimed the birds would actually starve to death while roosting, were it not for this daily torpid state.
Everything about the birds' metabolism, feeding requirements, and the fact that they have never been reported to fly at night, all suggest a 25-hour non-stop migration flight is highly improbable.
That said, nature quite often achieves the improbable. I would be delighted to be wrong, and be amazed by the birds one more time.

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Physics, Astronomy & Cosmology / Re: If the Universe is expanding, does this mean that space is expanding?

« on: 22/03/2020 14:46:18 »

I've seen no compelling evidence of space being created where there was none, or destroyed where there was some.

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Physics, Astronomy & Cosmology / Re: Is the Big Bang Theory Hokum?

« on: 09/03/2020 15:13:22 »

In the recovered papers he habitually misspells the name of Edwin Hubble as "Hubbel". Why?

"I" before "E", except after "C" is the rule...
Einstein missed it twice.

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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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Physics, Astronomy & Cosmology / Re: Will astronomers will be able to image Earth-like planets by 2025?

« on: 23/02/2020 16:47:28 »

I would certainly like to see more compelling and direct evidence on exoplanets...current methodology involves finding a star with a predictable, periodic dimming...then using standard orbital dynamics to postulate what size planet in what orbit might account for the dimming, in sort of a mini-eclipse. (Some also postulate the composition of the planet and presence of an atmosphere on these newly "discovered" exoplanets.)
I'm skeptical about the interpretation of the data...the researchers are specifically looking for exoplanets. When all you have is a hammer, everything looks like a nail.

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Physics, Astronomy & Cosmology / Re: If all ice melts will the world drown?

« on: 23/02/2020 16:02:17 »

Can an advanced society arise on a planet completely covered with liquid water?
Many life forms thrive in the oceans....lighting the campfires would appear to require a roomful of Einsteins...LOL

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Physics, Astronomy & Cosmology / Re: Is the Earth's orbital distance from the sun optimal for life?

« on: 22/02/2020 15:27:16 »

Some research has suggested that beyond a Goldilocks zone in our solar system, there is also a galactic Goldilocks zone, not based on "not too hot, not too cold,"  but "not too dense, not too sparse" star population.  A star too near the center (dense population of stars) of the galaxy is subject to all manner of intense radiation inhospitable to our form of life on any planets that form around it, as well as extreme gravitational forces.
A star too far from the center (sparse population of stars) of the galaxy will not have the history of supernovae incidence we believe necessary for the creation and distribution of heavier elements.

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Physics, Astronomy & Cosmology / Re: Is the Earth's orbital distance from the sun optimal for life?

« on: 18/02/2020 14:56:47 »

The slightly elliptical orbit of the Earth does produce "a bit" of variation in the distance...5000 km or 3.3 percent. This is within the "Goldilocks Zone"...not too hot, not too cold. It's a matter of some debate whether an orbit in the Goldilocks Zone is "necessary, but not sufficient" to support the genesis and evolution of life.
There are 181 moons in the solar system. Ours is BY FAR the largest relative to its' host planet. No moon means no tidal pools, the classical theory of the location of the genesis of life. Would a smaller moon serve as well? Nor are tidal influences the only consideration.
The moon's size is also credited with stabilizing the rotational axis of the Earth (though not entirely...the axis still precesses in a 28,000 year cycle). Absent a stabilizing moon, there would be a significantly higher rate of precession, with a corresponding disruption of the seasons on Earth. The effects this would have on the beginnings of life and evolution are largely unknown.
What's clear, (at least to me,) is that life, and certainly us, are not inevitable in the Goldilocks Zone.