
The Future of Humanity with Elon Musk: Interview by Neil DeGrasse Tyson - eroo
http://www.startalkradio.net/show/the-future-of-humanity-with-elon-musk/
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dave_sullivan
Couple points against humans physically exploring and colonizing space...

* Can't go faster than light (or even a large fraction of the limit)

* Cost. Look at price per compute vs price to bring something to space and tell me which trend seems more durable. Things will keep getting smaller while space exploration may not.

* Space sucks! Very inhospitable. I'd rather live in a biodome on a ravaged earth than mars.

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Alternative things to spend huge amounts of money on:

* LHC and other research on very small things

* More telescopes in space (light travels at the speed of light at least! Let it come to us instead of vice versa!)

* Encouraging trend of cheaper compute (not that it needs it)

* Brain to computer interfaces.

* Medicine

\---

What's to say some low mass x-ray binary systems aren't the final stage of
life evolution? Super efficient harvesting of the sun and everyone living in a
computer/black hole? Transcension hypothesis basically.

~~~
corysama
* Can't go faster than light (or even a large fraction of the limit)

It's my weak understanding that because of time dilation & length contraction
I could climb aboard a sufficiently powerful ship and travel 10,000 light
years before dieing of old age. But, when I got there, I would find that
10,000+ years had passed at the destination while they waited for me. And,
that if I made a return trip, Earth would be 20,000+ years older. But,
importantly, /I/ would not necessarily be 20,000 years older.

So, the speed of light still sucks, but it mainly sucks if you care about
returning home. If you give up on that goal, relativity does not say it's
impossible to travel to arbitrarily far locations in human-scale timeframes.

Am I misunderstanding?

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simonh
You're not missunderstanding. The problem is that to go that fast, even
assuming perfect conversion of mass to energy with zero losses, you'd need to
reach a speed of 0.999987 lighspeed. That gives a 200x time dilation factor so
the 10,000 year journay appears to take you only 50 years.

You'd need to convert approximately 100,000x the mass of your capsule to
energy to reach that kind of velocity, and the same again to slow back down at
the other end. So for a one way trip, the payload would be on the order of
1/1,000,000,000,000th of the mass of the ship.

For comparrison, that means a starship the size of a Saturn V would be able to
deliver a 3 milligram payload. If you assume even very slight efficiency
losses, the possible payload size collapses quickly. Remember, some of that
payload would need to be taken up by the propulsion system.

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mrfusion
Not if you powered the ship with a laser from a solar system, or pick up fuel
along the way.

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simonh
The problem with beamed power over that kind of distance is beam divergeance
(yes, even laser beams do diverge). Even very low wavelength beams, starting
with very wide aperture emitters, end up with a beam many times the diameter
of the solar system over these kinds of ranges. Good luck trying to capture
that energy for your spaceship.

The problem with picking up reaction mass along the way is, you need to lose
energy to accelerate it up to your own current speed first before you can
consume it as reaction mass to speed yourself up. As you get closer to
lightspeed, even with perfect, lossless conversion, e.g. at 0.9c you lose 90%
of the energy of the reaction mass bringing it up to your own velocity and get
only 10% of it for beneficial thrust. The total of required reaction mass,
which was already ludicrously huge for any practical payload, balloons
massively.

If you do actualy have energy conversion losses, those limit your maximum
possible speed. If you lose e.g. 1% of the energy you convert, then once
you're at 99% lightspeed, the energy you gain from burning the reaction mass
is the same as the energy you expended bringing it upto your own velocity. So
there's no net gain.

A top speed of 0.99C only gives you a time dilation factor of about x2.3 or
so.

And of course all of that is assuming magic fantasy tech with unbelievably
high efficiencies and negligibly sized engines and mass storage.

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mrfusion
Ok, true about the divergence, but how installing lasers along your flight
path? In principle that should work, right?

Or alternatively instead of placing stationary fuel pellets in your flight
path, have them accelerated by an external accelerator to as high a speed as
possible.

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simonh
You'd end up spending hundreds of thousands of years, and expending the
combined resources of many solar systems, just to deliver one guy in a space
capsule. What is the point of this journey anyway?

~~~
mrfusion
I was thinking you were saying it was physically impossible. But you're right
it's more of a cost issue.

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coldpie
Direct MP3 link (hopefully):
[https://api.soundcloud.com/tracks/197004056/download?client_...](https://api.soundcloud.com/tracks/197004056/download?client_id=0f8fdbbaa21a9bd18210986a7dc2d72c)

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ChikkaChiChi
We fleshbags have a pretty big problem when it comes to think outside of
ourselves; be it from a humanitarian, horological, or cosmological sense. Our
future is going to be pretty dire if we can't figure this problem out first,
and stop asking science to panhandle for scraps thrown to it by government
budgets that treat it like a monetary plague.

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kmeves
"houston we have a problem" .... most misquoted line. it is "houston we've had
a problem"

~~~
spoiledtechie
source?

~~~
tarentel
[http://www.hq.nasa.gov/alsj/a13/AS13_TEC.PDF](http://www.hq.nasa.gov/alsj/a13/AS13_TEC.PDF)

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amelius
The problem is of course, when Earth becomes inhabitable, who gets to decide
who can leave this planet?

I think it would be best for humanity if we first try to fix capitalism,
giving everybody equal opportunities.

~~~
JoeAltmaier
While I sympathize, it seems odd to segue from 'total environmental meltdown'
to 'scorekeeping in an imaginary game for imaginary points'. Which is what
capitalism is - a game for made-up dollar-points to motivate individuals to go
to work. Really, almost ever economic system is exactly that thing.

~~~
loganmhb
Your objection to the segue would make more sense if those "imaginary points"
didn't have the potential to e.g. purchase one of a limited number of tickets
off the planet (or any number of other life-changing/saving things). There's a
sense in which money isn't "real", but capitalism certainly isn't an imaginary
game for imaginary points.

~~~
wavefunction
Capitalism is just a social control system to replace previous control systems
like "religion" and "nationalism." It provides a general rules-set for the
average person to follow and believe in while allowing for greatly artificial
and generally negative social gradients and stratification.

For example, why should an ignorant hotel-heiress be afforded one of the
limited opportunities to flee the degraded Earth simply because she happens to
possess more imaginary points than a skilled technician or competent farmer?
Her real-social-utility is quite low compared to someone with functional
capabilities and her "great wealth" is directly derived from the environmental
degradation she is hoping to flee.

~~~
wavefunction
@spearchucker

"Intellectual currency" as you put it, is absolutely necessary on the
frontier, along with tenacity and a willingness to put up with physical and
mental hardship.

If there is a limit to the number of people who can flee a degraded earth, I
see no problem limiting it to people who can work together and yield their
intellect in service of survival. I'm almost positive that I would be one of
the ones left behind on Earth so this isn't some sort of personal superiority
complex.

I also think it's entirely appropriate for those who have benefited
disproportionately from the degradation of a system to use their extensive
resources in direct service to fix the problem.

Ultimately I'd like to believe that all persons interested in "escape" could
be accommodated but I also think most of us would have to remain and deal with
or fix the degradation.

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jondiggsit
One thing always bothers me about long distance travel in space: You increase
speed to get somewhere faster.... What about the slowing down part?!?!

Travel at near light speed is great, but how long did it take to accelerate to
that speed and how long does it take to slow down?

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mentos
Rather than solve the problem of not having enough resources to survive on
Earth, why not solve the problem of needing the resources to exist in the
first place?

Life will leave this Earth but not in the form everyone expects.

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mrfusion
Is there a transcript?

~~~
IkmoIkmo
Literally every other interview on film, audio or in writing he's ever done.
This guy literally rehashes interview questions, word for word, in a
particular order. It's actually hilarious once you've seen 10 of his
interviews, as well as mind numbingly boring. But I keep listening to them
hoping he'll say something new, as the things he does say are pretty powerful.

Hell if someone took 10 of his interviews and just made a video of the exact
same question answered the exact same way, that'd be pure comedy gold. You'd
trend on social media with that for sure. Things like 'lived on 1 dollar a
day', '5 most important things for humanity' and 'reason from first
principles', are just a few of the things he manages to say in every single
interview.

Anyway here's a quick transcript:

[http://www.autoevolution.com/news/elon-musk-tunnels-could-
ma...](http://www.autoevolution.com/news/elon-musk-tunnels-could-make-flying-
cars-unnecessary-mission-to-mars-in-11-years-93581.html)

~~~
someotheridiot
Well if the interviewers would stop asking the same stupid questions over and
over again he might get a chance to say something different. I felt this
interview was a completely wasted opportunity by NGT.

