General science thread

March 23rd, 2017 at 3:41:18 AM permalink
odiousgambit
Member since: Oct 28, 2012
Threads: 71
Posts: 1534
Came across this after pondering about the irregularity of eclipses - they do not constantly happen because the planes formed by the orbits of the sun and moon are off by about 5%, they say. But that they nearly concur is to be expected, the planes of all the planets and their moons etc all are *roughly* in the same plane [and I'm sure there are exceptions]. The same phenom with galaxies, thus the familiar disc shape. Why so? Why does the universe form discs and not spheres - at least for things that are large?

This question gets asked enough apparently, I found an answer on the internet, emphasis mine. The link has more.

Quote: link
Any big lump of gas and dust is likely to be rotating slightly. As it collapses under gravity the angular momentum is conserved - this means a large thing spinning slowly becoming a smaller thing must spin more quickly. As it spins more quickly it starts to flatten out into a disk - because stuff at the edges is pushed out. Then it gets complicated - but basically anything that isn't in the main plane of the spin as it turns from a sphere into a disk is captured by the disk and added to it. So whichever part of the sphere first lengthens out to become more like a disk will gradually attract all the other material and grow into a full disk.

Reference https://www.physicsforums.com/threads/why-is-our-galaxy-a-disc-and-not-a-sphere.418268/
Mustard:You like Kipling, Miss Scarlet? Sure, I'll eat anything [from movie]
March 23rd, 2017 at 1:10:44 PM permalink
Pacomartin
Member since: Oct 24, 2012
Threads: 687
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Quote: Evenbob

All the homes the rich built in England in the mid 1800's and are called castles today, really are not.


A castle is a large fortified building, or a stronghold. Now some of the castles (notably Windsor) have been turned into palaces as their military purpose has grown outdated, but other kinds of buildings should be referred to as palaces or manor homes.



Now some homes like the one pictured in southern Florida built in 2007 clearly are mimicking castle features like moats, and I suppose many homes in mid 1800's in England did the same thing.

Highclere Castle of Downton Abbey fame is possible the most famous manor home that is mislabeled as a Castle.
March 23rd, 2017 at 6:28:10 PM permalink
Evenbob
Member since: Oct 24, 2012
Threads: 106
Posts: 10927
Quote: Pacomartin

Highclere Castle of Downton Abbey fame is possible the most famous manor home that is mislabeled as a Castle.


On the show itself, they never refer to it
as a castle, the on site historian would
never allow it. It drives me nuts on the
real estate shows when any residence
built from stone pre 20th century in
England or Germany is now a 'castle'.

Highclere was built as a residence by
the same man who designed Parliament.
In the Wiki article it's wrongly referred
to as a castle several times. It was built
in the Anglo-Italian style in the mid
19th century as a private home, not
for military defense.
If you take a risk, you may lose. If you never take a risk, you will always lose.
April 4th, 2017 at 1:47:24 PM permalink
Nareed
Member since: Oct 24, 2012
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Pure idle speculation.

As dark matter detectors fail to detect dark matter, the thought arises: what if there is no dark matter?

Another thought arises as well: what if dark matter can only interact gravitationally and in no other form? Physicists call this a nightmare scenario.

Back to the first thought: if there is no dark matter, what then keeps galaxies whole when they spin too fast for their visible matter gravity to hold them together?

There are a bunch of theories that modify gravity to do this, notably Modified Newtonian Dynamics (MOND). But as yet no one has proven any observationally or experimentally.

So here's my idle speculation: what if there is a second attractive force in addition to gravity? damn, how would you go about finding proof for that!
If Trump where half as smart as he thinks he is, he'd be twice as smart as he really is.
April 4th, 2017 at 4:47:37 PM permalink
kenarman
Member since: Oct 24, 2012
Threads: 3
Posts: 832
Maybe it is the force of the Padres "God" he is also unseen and unproven.
"There is no sin but ignorance" Christopher Marlow
April 4th, 2017 at 6:52:00 PM permalink
Fleastiff
Member since: Oct 27, 2012
Threads: 48
Posts: 4434
Quote: Nareed
what if there is a second attractive force in addition to gravity?!
A weighty issue to ponder.
April 10th, 2017 at 2:04:32 AM permalink
odiousgambit
Member since: Oct 28, 2012
Threads: 71
Posts: 1534
What I thought I knew shattered:

A compass needle "usually does not point towards the magnetic North Pole [either]" - if it did, the difference between true north and magnetic north would be "irrelevant" in lower latitudes. "Currents in the Earth's core as well as deposits of iron and other chemical elements in the Earth's crust deflect the magnetic lines ... this causes vast, geographically irregular, and ever-shifting variations in the magnetic declination."

At least it still points north for the reason that the magnetic pole is up there somewhere - but it gets deflected. It is constant enough they can show the declination on a map at least. Quotes are from link.

https://www.timeanddate.com/geography/magnetic-declination.html
Mustard:You like Kipling, Miss Scarlet? Sure, I'll eat anything [from movie]
April 10th, 2017 at 2:53:14 AM permalink
Fleastiff
Member since: Oct 27, 2012
Threads: 48
Posts: 4434
Yeah, declination and deviation and all that Television Makes Dopey Children stuff TMDC for course corretions... that is why casinos always have a tiny little pocket compass in the craps pit. Someone will walk around the craps table and watch the compass for any sudden changes, particularly if someone in a wheel chair is playing at the table. The Pit Boss doesn't care what direction is north; he cares that the compass doesn't suddenly change its mind when the dice comes to any particular player. And if you go to far northern lattitudes, a magnetic compass can suddenly 'flip' which has lead astray small planes on foggy days. Search and rescue leaders often plot a pilot's "false courses" by considering the mistakes a pilot might have made involving incorrect addition or subtraction of magnetic course figures or the effects of local magnetite ore deposits.
April 19th, 2017 at 9:02:32 PM permalink
rxwine
Member since: Oct 24, 2012
Threads: 117
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http://www.businessinsider.com/psychedelic-drugs-lsd-ketamine-psilocybin-heighten-consciousness-2017-4

Quote:
Many people who have used psychedelic drugs will tell you that the substances expanded their consciousness.
That might sound like mystical garbage, but a new paper published in the journal Scientific Reports suggests it might be more true than anyone realized.


More at link.
No one has ever proven I am not God.
April 20th, 2017 at 1:42:11 PM permalink
Face
Administrator
Member since: Oct 24, 2012
Threads: 61
Posts: 3112
Quote: rxwine
http://www.businessinsider.com/psychedelic-drugs-lsd-ketamine-psilocybin-heighten-consciousness-2017-4



More at link.


It's not "mystical garbage", but any claim of mysticism is garbage indeed.

What you have with these things is connections, many of which shouldn't be made. You brain generally makes certain stimuli go to certain places to be processed by certain components. A very bad fart does not offend your ears, for example, cuz the brain ain't sending to the aural processor. It goes to the olfactory.

What psyche drugs do is make connections. Just as, say, coke binds to and triggers dopamine receptors, these drugs trigger the wires in your head. Instead of a linear path from A to B, a stimulus from A may trigger B, F, RSTLNE, 17, and avocado. This is the cause of the phenomena known as "tasting music" or "hearing colors".

Experiencing it, hell yeah, it seems and feels like some next level, 8th dimension, touched-by-the-hand-of-God mysticism. In reality, it's just boring ol' bio chem.
Be bold and risk defeat, or be cautious and encourage it.