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[Pwnzerfaust]

It makes perfect sense. I'm trying to explain it in a way a layman can grasp. Speaking of points of view asks the reader to place themselves from that perspective, and that aids in understanding.

[Il Palazzo]

No. That's simply wrong, or at best an example of lying to children. There's no reference frame of light, so one can't apply time dilation formula to light. If you tell people to place themselves in the perspective of a photon, then you're contradicting the light speed invariance postulate used in deriving relativity.
How does that help in understanding of anything? If you really need to make the 'relativity is weird, whoa' point, then say that light exist out of time or some such thing. At least you'll be correct.

[Pwnzerfaust]

The point I made, if you read it, was that there was no passage of time for a photon. You are being pointlessly and obnoxiously pedantic when the point was already plain.

[ChairmanPoo]

  Is... is movement, and by extention all the space that that movement takes place in, an illusion? 

Are you Zeno of Elea by any chance?

[Madman198237]

Why, yes, time and movement are illusions to some extent.

Time is a direct result of our partial ability to perceive the fourth dimension, via perceiving it as changes in three dimensions with an order.


Theoretically, photons do not experience time...maybe. Perhaps the answer lies in a solution of relativity (Somebody has probably already done this, but I don't know) that results in infinity, or zero, or some other otherwise-meaningless value that suggests photons don't experience time because time dilation at the speed of light is infinite.



Or perhaps you should stop considering photons as being capable of perceiving time.

[Starver]

From the (contrived) perspective of a photon, you also can establish that the observation of the entire universe rushing backwards past it such that origin rushes away and destination rushes in insyantaneously...  Because the observable (sic) universe around the photon suffers extreme lorentz contraction to make it a zero-length journey, hence the (perceived/experienced) instantaneity.

But when you're getting infinities out of equations, and you're not truly running a hotel to which an infinite number of infinitely capacitous tourist coaches have just rolled up unexpectedly, best not to actually pretend that it can be experienced.


So...  Where were we..?

Yes, movement is always relative.  Try juggling whilst on a train, in an airplane cabin or even just stood on the equator (1000 mph of spin, before adding/subtracting Earth's solar orbit, Sol's galactic orbit/drift, the galactic dance with Local Group partners, and the rest). Newtonian physics with an assumption of a stationary ground works well enough in the short term (and coriolis forces/vertical precession probably don't kick in enough to worry you, wherever you are).

Anyway, given that you only see the progress of light (or similar) via light (or similar) transmitting light in any direction to bounce back at you involves waiting exactly the same amount of time (see also Michelson-Morley). And, if you like, your experience of a photon sent one light-minute away and then bounced straight back to you is of a photon that takes two minutes to get to the destination (for each period of time the photon drifts away, you can't possibly experience it until the same period of time has passed to inform you that it has gotten to that point) then apparently zero time to return (all information that the photon has arrived and is coming back to you is exactly keeping pace with the original photon). Which rather confuses any concept of 'now'.  To you, 'now' at the mirror is a different thing from what the mirror thinks about your 'now' (it knows your 'now' happens until some time after/before its own version of the 'now', depending on what it is trying to match up to that).

Or, to put it another way, there is no such thing as light by which you see light, by any 'normal' understanding, so you're stuck trying to bend your mind round what you're left with.


Hmmmm...  I'm definitely going off into weird (if not 'wyrd') territory, which I'm not sure is helping.  Taking another break, before I try to confuse you about other points brought up, too.

[Max™]

Point to the east, most of the populated latitudes will be moving that way between 250 and 450 meters per second.

Locate the sun (might be tricky at night if you aren't used to keeping track of it, it should be off to my west-southwest and like 3 or 4 degrees below the plane perpendicular to my local vertical which has a name in astronomy but I'm completely fucking derping on it) and turn to face it, then in the northern hemisphere face south and point at it with your left hand while your right hand is roughly 90 degrees away, or straight out at shoulder height basically, so in the southern hemisphere you simply face north, point at the sun with your right hand, and set your left 90 degrees away again. You're moving about 29,800 meters that way every second.

Now turn towards the northern constellations and find the big blue-white star a little ways off from the dippers, that should be Vega, and we're heading roughly in that direction at 220,000 meters per second.

[Madman198237]

Direct overhead for an observer is "zenith".

[RedKing]

NASA to announce a new slate of Kepler exoplanet discoveries today. (Actually, they're streaming it live now.)

EDIT: 10 new planet candidates in habitable zones, 3-4 of those around G-class stars.

DOUBLE-EDIT: This is the final batch from the first Kepler mission.

TRIPLE-EDIT: 49 planets in the habitable zone with a mass <1.8 Earths. This is out of 0.25% of the sky, and with a 1/200 chance that a given planet is transiting its star from Earth's POV. That leaves room for a hell of a lot of planets still out there.

[inteuniso]

NASA to announce a new slate of Kepler exoplanet discoveries today. (Actually, they're streaming it live now.)

EDIT: 10 new planet candidates in habitable zones, 3-4 of those around G-class stars.

DOUBLE-EDIT: This is the final batch from the first Kepler mission.

TRIPLE-EDIT: 49 planets in the habitable zone with a mass <1.8 Earths. This is out of 0.25% of the sky, and with a 1/200 chance that a given planet is transiting its star from Earth's POV. That leaves room for a hell of a lot of planets still out there.

Well, the organic proto-molecule for amino acids and DNA is literally a Carbon Dioxide acid attached to itself (There's no mention of pure 2-COOH but pot-smoking hippies isolate it all the time so they can get to their cannabinoids so it's definitely there), so it's looking more and more likely that carbon-based lifeforms are plentiful. probably.

[RedKing]

NASA to announce a new slate of Kepler exoplanet discoveries today. (Actually, they're streaming it live now.)

EDIT: 10 new planet candidates in habitable zones, 3-4 of those around G-class stars.

DOUBLE-EDIT: This is the final batch from the first Kepler mission.

TRIPLE-EDIT: 49 planets in the habitable zone with a mass <1.8 Earths. This is out of 0.25% of the sky, and with a 1/200 chance that a given planet is transiting its star from Earth's POV. That leaves room for a hell of a lot of planets still out there.

Well, the organic proto-molecule for amino acids and DNA is literally a Carbon Dioxide acid attached to itself (There's no mention of pure 2-COOH but pot-smoking hippies isolate it all the time so they can get to their cannabinoids so it's definitely there), so it's looking more and more likely that carbon-based lifeforms are plentiful. probably.

tldr; Pot is life, man.

[Egan_BW]

Makes it look likely that there's other life in our galaxy, which is awesome.

[LordBaal]

Now Fermix paradox could be that inteligent life is rare. Or sufficiently advanced life is rare to occur twice near enough in terms of time and distance to have any kind of comunication, or at least anything meaningful beyond your ocational Wow! signal.
Either that or Necrons and/or Tyranids are real.

[MetalSlimeHunt]

We're still not quite there on the "Earthlike planets" level of the Fermi paradox. While these exoplanets are indeed rather more Earthlike than expected, even the most Earthlike of them are still more Mars or Venuslike. The answer can still be that true Earth analogues are extremely rare, but everything around that jackpot is fairly common.

[origamiscienceguy]

How vital is the moon to life evolution?  From what I understand, a moon as big as ours is a rare occurance.