Origins of life partially explained?

[jschild]

http://www.sciencedaily.com/releases/2009/01/090109173205.htm

Very interesting article about how some scientists have created very simple RNA molecules that can self replicate indefinitely.

This is the first proof of concept that life (and DNA) could have evolved from RNA (which is far simpler than its cousin, DNA).

This doesn't prove that this is how life arose, but it does greatly strengthen the possibility, however.

[Daedelus84]

Thanks for linking that, it was a very interesting read.

[Leord]

Oho, cool jschild! An article just to my liking =)

[TPMdm]

Interesting article though I might take a slight exception to the title of the thread in relation to it :wink:

[jschild]

Interesting article though I might take a slight exception to the title of the thread in relation to it :wink:

Thats why I added the question mark. Also why the word explained (as opposed to something like proven) was used.

It proves that the concept that RNA could have reproduced, and thus have been a precursor to DNA, was possible.

Unless someone makes a time machine, there is no way to fully "prove" that is what happened short of the RNA mutating into DNA right before our eyes, which given the likely timeframes, makes that a non-starter.

[surodat]

Unless someone makes a time machine, there is no way to fully "prove" that is what happened short of the RNA mutating into DNA right before our eyes, which given the likely timeframes, makes that a non-starter.

I invented a time machine.

Unfortunately, it only allows us to go forward in time.


Very slowly.

[jschild]

As She-Hulk once pondered, if we cannot go faster than light, does that likewise mean we cannot go slower than dark?

[TPMdm]

As She-Hulk once pondered, if we cannot go faster than light, does that likewise mean we cannot go slower than dark?

My favorite color is sideways.

speaking of colors I'm leery of posting this in it's own thread but THIS was pretty cool to me:
http://arstechnica.com/news.ars/post/20090115-mars-makes-methane-sign-of-life-or-geology-at-work.html

[jschild]

My favorite color is sideways.

speaking of colors I'm leery of posting this in it's own thread but THIS was pretty cool to me:
http://arstechnica.com/news.ars/post/20090115-mars-makes-methane-sign-of-life-or-geology-at-work.html

Very cool. Correct me if I am wrong, but didn't the Viking landers detect methane during it's biological experiments when the soil was given "food"?

Very interesting but I wouldn't be shocked if we found microbial life on Mars. We have discovered such hardy life on Earth that if Mars had time to develop life, that it wouldn't find some niche to hold onto. I would be absolutely shocked however if anything other than single cell life was found there.

[Shellar]

I invented a time machine.

Unfortunately, it only allows us to go forward in time.


Very slowly.
I invented a time machine that can go backwards in time.
Unfortunately, the minimal possible travel distance is much greater than the current age of the Universe.

[rgirty]

I was under the impression that the faster you traveled, the slower that time would actually pass?

Correct?

I had the idea that if this were true a large circular track could be built on which a craft would travel at an extreme rate of speed (of course this technology does not exist).

The people riding in this craft would not experience the same passage of time as individuals who were on the ground near it, or anywhere else on the planet.

Thus the people on the craft are in sort of a time suspension.

The crafts could then be built in ratios.

For example, the 1 year craft. If you board this craft, 1 year would pass on earth while only 1 day would pass on the craft.

This might be used if a food/water supply was low. A large portion of the society could board the craft while the remainder stayed behind to grow a year's worth of crops and or livestock.

A 5/10/20/30 year craft (obviosly, there would be many selections) that would act in a manner such as the cryogenic freezing of people's heads.

If you have a terminal disease, in the final stages you could board a 5/10/20/30 year craft with the thought in mind that a cure would be available.

The people on the ground of course would have records of who was on what craft and have the treatment available upon the craft stopping.

I know we don't have any tech to do this, just a thought I had.

[TPMdm]

Interesting idea rgirty. I'm glad you are aware of some of the current engineering limitations of the proposal :wink: (going fast enough without killing the passengers is probably #1)

Sounds like it would make a cool story

[jschild]

Rgirty is correct. The faster you go, the slower time goes, in reference to those not going that same speed. IE, no matter how fast you went, time would seem to flow as normal as any other time. Let's say you could fly to Proxima Centauri, the closest star to us at about 4.26 LY. If you could safely travel from point A to B at the speed of light, those on board would not notice any real passage of time. The trip would appear instant to them, while those on Earth would age 8.52 years.

This time dilation effect only becomes readily apparent at very large speeds (>90% speed of light).

And regards to TPMdm, traveling that rate of speed would not be harmful. It would only be the acceleration/deceleration that would pose problems (acceleration greater than 1g for any length of time would not be healthy) and hitting even small objects at that speed would be by far the greatest threat.

[rgirty]

Meh, just a thought I had.

I can't imagine the anxiety of stepping off a 30 year craft wondering what had changed or if there is a cure for whatever you were dying of. If no cure, stepping right back onto the craft for another 30 years.

Would your wife/kids be allowed to go? Would you want to take them? How would your finances/belongings be handled while you are gone..

Kinda OT sorry to go off track.


JSchild, I always wondered why the people aboard the starship enterprise aged accordingly with their old buddies from star fleet while they were all flying around at warp 9 for different intervals of time.

[jschild]

Star Trek is kinda confusing. They don't actually travel faster than the speed of light (though they can reach it or almost).

The ship's warp speed is actually a measurement of the warpage of space (and thus shortening of distance) if I remember right. IE, the speeds it goes (like 100 times the speed of light) is only a relative measure. They might travel the distance at close to the speed of light, but actually are warping the space so they are traveling 1/100th the distance. So it only "appears" they traveled that fast when in fact they never violated the light barrier.

[surodat]

They did sort of the same thing in Ender's Game - sending a guy on a space trip for 50 years at close to the speed of light just to keep him around for later. (He admitted it was a pretty boring trip.) :D

There was an interesting discussion of cryogenics in James Halperin's The First Immortal. Although a shamelessly optimistic work, it does wander through some interesting territory concerning 'freezing' people - both literally and socially.

[rgirty]

Star Trek is kinda confusing. They don't actually travel faster than the speed of light (though they can reach it or almost).

The ship's warp speed is actually a measurement of the warpage of space (and thus shortening of distance) if I remember right. IE, the speeds it goes (like 100 times the speed of light) is only a relative measure. They might travel the distance at close to the speed of light, but actually are warping the space so they are traveling 1/100th the distance. So it only "appears" they traveled that fast when in fact they never violated the light barrier.

So what you are saying is that they were in fact creating a semi-wormhole?

Kinda confusing indeed because scotty was in danger of the "ship flying apart" several times..

hmm!

[surodat]

Wait, and how did chases work? If one ship was bending space at a particular "warp" and a different ship at a different "warp" how can one be shown to be "following" the other?

Wouldn't they be following completely different trajectories?

(Haha, nerds!)

[mesonm]

I was under the impression that the faster you traveled, the slower that time would actually pass?


Actually, it is much more complicated than that...

Look up special relativity by Einstein, as modified by Lorentz.

http://en.wikipedia.org/wiki/Special_relativity

[rgirty]

I'm aware of special relativity, in fact the twin paradox http://en.wikipedia.org/wiki/Twin_paradox was part of what I was thinking about when I thought of the craft traveling idea.

Gravitational time dialation http://en.wikipedia.org/wiki/Gravitational_time_dilation in reference to the accelerated reference frame http://en.wikipedia.org/wiki/Accelerated_reference_frame are the two issues that make me kind of fuzzy.

Of course I'm not a physicist, but the pound rebka http://en.wikipedia.org/wiki/Pound-Rebka_experiment experiment at least proves this is slightly possible, if only in theory.

From what I can gather here the accelerated craft passing through time more slowly not only depends on speed, but in altering the gravitational field or creating one of its own.

Perhaps frame dragging, or even rotational frame dragging may be the meat of it?

Rotational frame-dragging (the Lense-Thirring effect) appears in the general principle of relativity and similar theories in the vicinity of rotating massive objects. Under the Lense-Thirring effect, the frame of reference in which a clock ticks the fastest is one which is rotating around the object as viewed by a distant observer. This also means that light traveling in the direction of rotation of the object will move around the object faster than light moving against the rotation as seen by a distant observer. It is now the best-known effect, partly thanks to the Gravity Probe B experiment.

http://en.wikipedia.org/wiki/Frame-dragging

In any case the pound rebka experiment is fascinating, to me at least. I just wish I was smart enough to fully understand how all this works together.

[jschild]

As you increase in speed, so does your mass. The reason that no physical (or at least nothing that has mass) can reach or exceed the speed of light is that its mass would be infinite at the speed of light. Therefore, more energy is needed to keep accelerating. Space and time is distorted the faster and more massive the object becomes. Massive objects warp space and time without needing to move much, but even small particles with mass will eventually reach a point that their mass and speed warps space/time.

As to star trek, its not a wormhole. Essentially space in front of the ship is being contracted, while space behind the ship is expanding, essentially allowing the ship to "surf" on a wave of space-time curvature. The greater the warpage/contraction in front of the ship, the "faster" it goes, since the distance traveled is shortened more and more.

Scientists actually have ideas on how to do this in real life, but it would require the ability to generate large amounts of exotic matter (exotic matter repulses instead of attracts matter, allowing you to warp it). http://en.wikipedia.org/wiki/Negative_matter

[TPMdm]

As to star trek, its not a wormhole. Essentially space in front of the ship is being contracted, while space behind the ship is expanding, essentially allowing the ship to "surf" on a wave of space-time curvature. The greater the warpage/contraction in front of the ship, the "faster" it goes, since the distance traveled is shortened more and more.


A theory among the StarWars nerds is that this is why Han Solo refers to his Kessel Run accomplishment in distance rather than time.

"She's the ship that made the Kessel Run in less than 12 parsecs." parsec is a measure of distance not time or speed. It's like saying "I ran a marathon in less than 5 miles". Which makes sense if you are bragging about how much space you can bend.

I propose a new warp measurement based on one of the most famous benders of all time: The Beckham Scale :grin:

[jschild]

Actually in one of the books its kinda explained (this was when they were still half decent and mostly being written by Zahn). Its a very dangerous zone of space, with all kinds of obstacles and most people fly around it, thus making the trip longer. Han apparently found a shortcut that is dangerous but much straighter, allowing him to make the trip much shorter AND avoiding the empire patrols.

-God...I'm a geek.

[rgirty]

Very interesting, maybe we went way OT but still... interesting.

[WatcherZero]

If I remember right Kessel was in a dense area of space and SW's Hyperspace drives cant go through matter so they have to avoid star systems doing several course corrections along the way.

update:
This explains it better, the Maw is a collection of dozens of small black holes.

"The gravity distortions of the nearby Maw warp space makes it tremendously difficult to navigate a starship through it without a highly skilled pilot. Ships approaching Kessel take long winding courses through the Maw to avoid the danger of being sucked into a gravity well. On a mission where he was pressed for time, Han Solo was able to navigate the shortest course through the Maw in "less than twelve parsecs." With the boosted speed of the Millennium Falcon, Solo managed to haul a load of spice for the Hutts in record time and earned a reputation as a top-rate smuggler."

As to startrek, the warp engine as JSchild says warps space making it smaller in front and larger behind, however the riding a wave bit is incorrect, ships use their normal sublight impulse engines for propulsion at warp speeds with the warp bubble allowing the conventional propulsion to break the speed of light rules. Theirs a lot of tech blunders during the show though where they say their impulse engines damaged or offline but still manage to warp to safety, but then this is the show that brought us such concepts as Plot armor and plot shields.

[jschild]

If I remember right Kessel was in a dense area of space and SW's Hyperspace drives cant go through matter so they have to avoid star systems doing several course corrections along the way.

update:
This explains it better, the Maw is a collection of dozens of small black holes.

"The gravity distortions of the nearby Maw warp space makes it tremendously difficult to navigate a starship through it without a highly skilled pilot. Ships approaching Kessel take long winding courses through the Maw to avoid the danger of being sucked into a gravity well. On a mission where he was pressed for time, Han Solo was able to navigate the shortest course through the Maw in "less than twelve parsecs." With the boosted speed of the Millennium Falcon, Solo managed to haul a load of spice for the Hutts in record time and earned a reputation as a top-rate smuggler."

As to startrek, the warp engine as JSchild says warps space making it smaller in front and larger behind, however the riding a wave bit is incorrect, ships use their normal sublight impulse engines for propulsion at warp speeds with the warp bubble allowing the conventional propulsion to break the speed of light rules. Theirs a lot of tech blunders during the show though where they say their impulse engines damaged or offline but still manage to warp to safety, but then this is the show that brought us such concepts as Plot armor and plot shields.

Star Trek was noterious for having bad writers who never read any of the "tech bibles" and thus breaking canon on regular basis.