Yes, WPF apps take a long time to start up the first time. It must be some sort of library overhead since if you start the same app (or any other WPF app) after the first time it's near-instant. Other than that, I haven't hit any irreconcilable speed issues myself; virtualizing containers have been enough. I've never used Qt though I've heard good things as a rule.
I don't let myself read Conservapedia articles on topics I actually care about anymore. That includes some of their math articles, most of their science articles, and all of their gay articles. It makes me too angry to be unable to correct their ridiculousness. As an example, here's a gem from the Elementary Proof article:
elementary proofs minimize the underlying assumptions, as in avoiding the assumption that there is a unique, algebraically manipulable square root of negative one
(-1 has two square roots, -i and i, not one; the construction of the complex numbers from the real numbers is basic and entails no extra assumptions in standard formulations.)
Andy Schlafly, the Conservapedia head-honcho, has a problem with the rigorousness of imaginary numbers. It's particularly bizarre when you consider Andy has a Bachelor's in Electrical Engineering from Princeton. His brother Roger has a Ph.D. in mathematics from Berkeley (an excellent school for math; his adviser was even the famous mathematician Isadore Singer of Atiyah-Singer Index Theorem fame) and contributes some to Conservapedia.
Anywho, it's mostly best to just stay away, though a while ago I did have a laugh at the Obama article. He's "also known by the alias Barry Soetoro" and is "probably the first Muslim President". About his birth certificate,
After many leading conservatives including the leadership of this site and brilliant business man Donald Trump AKA "The Donald" called for Obama to release his birth certificate he did on April 27.
I did mean to put that I am a total um "not a physics guy" just the armchair piece-together-what-i-can-repeat dreamer type.
I know:). I don't think any physics people would use the phrase "Lord Nibbler poo at the completion of a black hole" or make the mistake of thinking a black hole has infinite mass and/or violates conservation of mass. But thank you for your honesty regardless.
Yup, that's what I meant to imply. I imagine it would be extremely difficult to measure such "ghost effects" in exotic matter. One could make a nice sci-fi story out of them, though.
Do you have any theoretical reason to believe dark matter would be visible in the usual sense as it falls into a black hole (that is, by emitting photons), or is it just an interesting idea?
Bugs too. I love TES games, but the last three have been completely riddled with bugs--eg. Morrowind can be beaten in about 4 minutes with the help of Sunder/Keening swaps (to be fair, this got patched). Considering the number and variety of quest bugs, I like to play TES games on the PC so I have access to the console so I can fix/workaround them. I can't imagine the same things in an MMO, it would be disastrous.
Events like this are rare; they probably only happen every 100,000 years or so per galaxy. So the astronomers looked at 100,000 galaxies, giving them good odds they’d see something like this once per year. Their gamble paid off.
Here are some relevant bits of physics you might not be aware of:
* White holes are somewhat shaky. From their Wikipedia article,
However, this region does not exist for black holes that have formed through gravitational collapse, nor are there any known physical processes through which a white hole could be formed.
There are apparently solutions to the Einstein field equations giving black/white hole pairs, but black holes do not need white holes to exist.
* There is an interpretation of antimatter in quantum field theory as matter traveling backwards through time (that phrase is very imprecise unfortunately). More details here; I'm not qualified to really discuss it as I'm just a mathematician with an interest in physics. Still, perhaps in vague terms your parallel universe dichotomy can be replaced with the two directions of time.
* Black holes have infinite density, not infinite mass.
* Hawking radiation allows black holes to evaporate away if they don't eat up enough mass.
Uh, antimatter is seen all the time. Heck, the "P" in "PET scan" stands for "positron", the electron's antiparticle. As for dark matter, it's "seen" in gravitational effects, which is admittedly indirect and somewhat inconclusive. Still, humans are rather biased. The matter you're made out of is mostly quarks and electrons. Quarks are affected by all four fundamental forces: (G)ravity, (E)lectromagnetism, (W)eak, and (S)trong. Electrons are only affected by GEW. Neutrinos have just GW and are therefore hard to detect. Maybe there's matter that's just affected by G; it would only show up on cosmological scales like dark matter seems to.
Who knows? Maybe there's a whole segment of matter humans are unfamiliar with which interacts very little with the matter we know about but interacts with itself in complicated ways. Maybe there are dark matter solar systems populated by dark matter people who are just as confused as we are about the weird gravitational anomalies caused by our otherwise invisible existence. Communicating through gravity would certainly be an interesting challenge! I don't really believe this, but my point is basically the same as Hamlet's: "There are more things in heaven and earth than are dreamt of in your philosophy"--that is, it's arrogant to expect humans to be in a position to observe all the parts of the universe. Perhaps some things are just hidden.
I agree this is off-topic, but I really like WPF. It has a steep learning curve and a lot of quirks, but data binding, templates, and the layout system save a lot of time and make things look nice. The people complaining about WPF in your link often called themselves old; maybe that's the real problem (I'm quite young).
I actually spent a few seconds trying to rework the punchline to get around that little inconvenience, but no dice. I'm sure Feynman thought the same thing and I'm pretty sure he was smarter than I am (certainly he was quicker), but he apparently wasn't able to get around it either.
I read evidence for an argument once that concluded smart people exhibit non-standard behavior of all kinds. Unfortunately I didn't get to read their reasoning, though I do remember two of their examples: night owls and homosexuals. My college dorm had a ridiculously high percentage of both, and everyone there would have been at the uppermost end on general population intelligence tests, so the conclusion is at least consistent with my personal anecdotal evidence. Non-right-handedness among your company's IT workers might be caused by the same underlying mechanism. I'm probably best described as cross-dominant myself: I write with my left hand, use forks alone with my right, use knife+fork with either, use the mouse with either, use right to masterbate, throw right-handed, and have finer motor control over my left.
but without demonstrating it to be true and to what degree I cannot see how any meaningful conclusions can be drawn.
Well, if the model predicts reality accurately, one concludes the premises are plausible or likely. It's not the greatest form of evidence, but it's enough for many purposes. I've seen physicists ignore the lack of mathematical rigor in their arguments, and as far as I can tell the justification is the same: the results are pretty good, so the steps taken must have been correct.
Haha, thank you. Just to be clear, my original post left off where Feynman did, before CP violation was discovered.
YouTube'ing Feynman is a great way to spend some free time. I wish we had videos of some of the other great minds in history--what I wouldn't give to watch Gauss say, "here's how I did it"!
if you ever meet a perfect version of yourself constructed by aliens from radio transmissions, don't shake their hand.
For those who don't know, this refers to a story in the Feynman Lectures on Physics. Here's my version; I've taken some liberties.
Imagine you're on the phone with an alien who speaks English, except they don't know what "left" and "right" mean. You want to explain it to them so they know which tentacle they should use to shake the right-handed President's hand if they should ever meet. The alien can be anywhere in the universe, so you can't refer to stellar positions or similar, leading you to devise an experiment for them to perform.
Your initial attempts use gravity, electricity, and magnets, but you notice each experiment comes out essentially the same if you swap "right" and "left"--for instance, you could give the alien instructions for making a clock in hopes of defining "right" using clockwise rotation, except if the alien made the clock exactly backwards by reversing the notion of "left" and "right", they wouldn't be able to tell. A particle physicist happens by and tells you about a magical experiment involving the weak nuclear force that *does* distinguish left and right inasmuch as the experiment fails if the alien screws up "right" and "left" and succeeds otherwise. (For the curious, some more details here and here.) Great, problem solved.
"But wait!" the physicist says. "The alien needs to use regular matter instead of antimatter in the experiment. The results will be reversed otherwise! Come to think of it, I have no idea how to tell them the difference between matter and antimatter. If you ever meet them and they start trying to shake your left hand, RUN, since the alien will be made of antimatter!"
This discussion made me wonder where the new particle falls in standard particle classifications. I've always been curious so I finally looked it up. My notes are below if anyone else is curious. I abbreviated the fundamental forces as (G)ravity, (E)lectromagnetic, (W)eak, (S)trong.
(1) Elementary particles: indivisible (probably). Includes fundamental fermions and bosons.
(A) Fundamental fermions: obey Pauli exclusion principle and Fermi-Dirac statistics. Includes quarks and leptons.
(I) Quarks: six flavors; combine in groups of two or three; interacts with GEWS. The "S" allows atomic nuclei to exist.
(II) Leptons: six types, three charged, three not.
(a) Charged leptons: mostly, the electron. Interacts with GEW. The "E" there makes chemistry work.
(b) Uncharged leptons: neutrinos. Interacts with GW, so not much with ordinary matter.
(B) Fundamental bosons: obey Bose-Einstein statistics, disobey Pauli exclusion principle. Includes gauge bosons, Higgs boson, and gluons.
(I) Gauge bosons: force carrying particles. Photons carry E, W- and Z-bosons carry W, gluons carry S.
(II) Higgs boson: would explain the non-masslessness of some fundamental particles. Currently the only unobserved standard model particle.
(III) Graviton: would carry G. Theoretical status somewhat uncertain; not a standard model particle; currently unobserved.
(2) Composite particles: composed of multiple elementary particles. Includes hadrons, atoms, molecules.
(A) Hadrons: two or three quarks held together by S. Includes baryons and mesons.
(I) Baryons: fermions made of three quarks. Most famous examples are protons and neutrons. Huge variety--~hundreds or more depending on how you count.
(II) Mesons: bosons made of two quarks. All unstable. Huge variety--~hundreds or more depending on how you count..
Note that each particle has an anti-particle, where each composite particle's anti-particle is obtained by replacing the constituent elementary particles with corresponding anti-particles.
The \Xi_b^{*0} particle (the summary left off the 0 for some reason...) is a baryon, so it falls under (2AI) in the above list. In light of the variety of the hadrons and their composite particle nature, this story isn't terribly exciting (at least to me).
[Please correct any mistakes; I'm not a physicist.]
This! Him skipping this vote make me put him firmly in the 'fuck this guy' pile.
Wow, I'm impressed. If you take that much care in all your decision making, in Ron Paul's shoes I would certainly be honored to have your vote for president!!1
The vote was moved up a day unexpectedly and all the "not voting" people combined wouldn't have changed the outcome. You could at least withhold judgement until knowing his side of the story; perhaps he was campaigning and planned to return for Friday's vote, I dunno (and I'm nearly certain you don't either). But no, nevermind, let's rush to judgement--Fuck RON PAUL! Gah, you even complain about your own past judgement-rushing in the same post you rush to judgement again.
I'd like to note Paul did not vote "Present" (which means you're not added to the Yea or Nay tally but were around for the official vote). Maybe he does deserve scorn for not voting against it, but I don't have enough info to say, and as far as I can tell neither does anyone here.
The bit of my post you quoted has nothing to do with your comments, which in turn have little to do with my post. I'm sorry, but did you even read it? My post is not about FTL communication whatsoever. It's about traveling between distant planets in a single human lifetime using the known relativistic effect of length contraction.
Does that mean we'll encounter life from other planets? Perhaps not. That depends on whether any forms of FTL ever prove feasible, beyond which there's the roll of the dice of the rarity of planets with life.
People always seem to forget (or never learned) length contraction. If you're in a spaceship pointed at the center of the galaxy, as you approach the speed of light the length between you and the center of the galaxy contracts. The contraction factor (the Lorenz factor, I'll call it g) is determined by your speed. It's 1 when you're at rest compared to the center of the galaxy and goes to infinity as you approach the speed of light. To give some actual numbers, if you want to travel 30,000 (rest frame) lightyears in 1 year, you'd need a speed of about 0.99999999945c and a Lorenz factor of about g=30021.
Mass dilates as well, meaning that an object at this speed has more kinetic energy than the classical KE = 1/2 mv^2 formula. The special relativistic formula giving the energy required to bring a mass m at rest to a speed encoded in the Lorenz factor g is mc^2 (g-1). At the above speed, g-1 = 30020, so you would need to convert 30020 times as much mass as your spacecraft has to energy in order to get to the required speed. For comparison, for a 100 metric ton spacecraft this is around 0.7 times as much energy as the sun puts out each second.
Actually doing this is certainly impossible today and for the near future, but perhaps one day it will be feasible to send small crafts between worlds. It's important to note that, for the people 30,000 light years away, your journey would take approximately 30,000 years. But to you it would take only 1 year. If you made a return trip, Earth would be more than 60,000 years different. The point is that you could make the journey in a single human lifetime, with an efficient enough propulsion system, so long as you were alright with both earth and your destination experiencing a large passage of time.
It gets really unintuitive if you go to the rational numbers which are dense.
Actually I disagree. There is a simple way to visualize the countability of the rationals, which is a variation on the following (I believe standard) enumeration that I won't formalize: 1/2 1/3, 2/3 1/4, 2/4, 3/4 1/5, 2/5, 3/5, 4/5... I realize numbers are repeated but it's simple conceptually to cut out the duplicates and, if you want, to repeat the process in each interval [n, n+1]. The picture corresponding to the version I've written is of course equally spaced points with ever finer spacing, and for any rational number with a given denominator that number will be hit at that denominator's stage.
By "unintuitive" I meant that, for finite sets, proper subsets are smaller in the sense above, whereas infinite sets do not possess this familiar property. Of course it's subjective:).
And of course once you are there, with a dense set of numbers, it is completely unintuitive that you can still put numbers "in between". And even more numbers than you already have.
Hmm... sorry, I again disagree. Rational numbers have repeating decimal expansions; if this fact is intuitive (I believe it is, though a rigorous proof may not be), then picking a number that doesn't have a repeating decimal expansion (easy to do) means you've picked an irrational, so there are numbers "between" the rationals. I would at least find it quite weird if the set of infinite binary strings and the set of finite binary strings had the same cardinality--I would very much want to know the injection. Since I find the converse of Cantor's conclusion unintuitive, I find Cantor's conclusion intuitive. Again, though, the phrase is subjective.
Slashdot Mirror
Yes, WPF apps take a long time to start up the first time. It must be some sort of library overhead since if you start the same app (or any other WPF app) after the first time it's near-instant. Other than that, I haven't hit any irreconcilable speed issues myself; virtualizing containers have been enough. I've never used Qt though I've heard good things as a rule.
They're called miniPads.
any history or development on subjects focus solely on American aspects.
Actually that's part of the point. From their Quick Reference page,
Conservapedia articles' tone, style, and content should be written with an American, conservative and/or Christian orientation or focus.
"pornography leads to terrible crimes against women"
Gay porn doesn't. I'm sure "The Trustworthy Encyclopedia" mentions this somewhere, or soon will :).
I don't let myself read Conservapedia articles on topics I actually care about anymore. That includes some of their math articles, most of their science articles, and all of their gay articles. It makes me too angry to be unable to correct their ridiculousness. As an example, here's a gem from the Elementary Proof article:
elementary proofs minimize the underlying assumptions, as in avoiding the assumption that there is a unique, algebraically manipulable square root of negative one
(-1 has two square roots, -i and i, not one; the construction of the complex numbers from the real numbers is basic and entails no extra assumptions in standard formulations.)
Andy Schlafly, the Conservapedia head-honcho, has a problem with the rigorousness of imaginary numbers. It's particularly bizarre when you consider Andy has a Bachelor's in Electrical Engineering from Princeton. His brother Roger has a Ph.D. in mathematics from Berkeley (an excellent school for math; his adviser was even the famous mathematician Isadore Singer of Atiyah-Singer Index Theorem fame) and contributes some to Conservapedia.
Anywho, it's mostly best to just stay away, though a while ago I did have a laugh at the Obama article. He's "also known by the alias Barry Soetoro" and is "probably the first Muslim President". About his birth certificate,
After many leading conservatives including the leadership of this site and brilliant business man Donald Trump AKA "The Donald" called for Obama to release his birth certificate he did on April 27.
I did mean to put that I am a total um "not a physics guy" just the armchair piece-together-what-i-can-repeat dreamer type.
I know :). I don't think any physics people would use the phrase "Lord Nibbler poo at the completion of a black hole" or make the mistake of thinking a black hole has infinite mass and/or violates conservation of mass. But thank you for your honesty regardless.
Yup, that's what I meant to imply. I imagine it would be extremely difficult to measure such "ghost effects" in exotic matter. One could make a nice sci-fi story out of them, though.
Do you have any theoretical reason to believe dark matter would be visible in the usual sense as it falls into a black hole (that is, by emitting photons), or is it just an interesting idea?
Bugs too. I love TES games, but the last three have been completely riddled with bugs--eg. Morrowind can be beaten in about 4 minutes with the help of Sunder/Keening swaps (to be fair, this got patched). Considering the number and variety of quest bugs, I like to play TES games on the PC so I have access to the console so I can fix/workaround them. I can't imagine the same things in an MMO, it would be disastrous.
From the article,
Events like this are rare; they probably only happen every 100,000 years or so per galaxy. So the astronomers looked at 100,000 galaxies, giving them good odds they’d see something like this once per year. Their gamble paid off.
Here are some relevant bits of physics you might not be aware of:
* White holes are somewhat shaky. From their Wikipedia article,
However, this region does not exist for black holes that have formed through gravitational collapse, nor are there any known physical processes through which a white hole could be formed.
There are apparently solutions to the Einstein field equations giving black/white hole pairs, but black holes do not need white holes to exist.
* There is an interpretation of antimatter in quantum field theory as matter traveling backwards through time (that phrase is very imprecise unfortunately). More details here; I'm not qualified to really discuss it as I'm just a mathematician with an interest in physics. Still, perhaps in vague terms your parallel universe dichotomy can be replaced with the two directions of time.
* Black holes have infinite density, not infinite mass.
* Hawking radiation allows black holes to evaporate away if they don't eat up enough mass.
Uh, antimatter is seen all the time. Heck, the "P" in "PET scan" stands for "positron", the electron's antiparticle. As for dark matter, it's "seen" in gravitational effects, which is admittedly indirect and somewhat inconclusive. Still, humans are rather biased. The matter you're made out of is mostly quarks and electrons. Quarks are affected by all four fundamental forces: (G)ravity, (E)lectromagnetism, (W)eak, and (S)trong. Electrons are only affected by GEW. Neutrinos have just GW and are therefore hard to detect. Maybe there's matter that's just affected by G; it would only show up on cosmological scales like dark matter seems to.
Quoting myself,
Who knows? Maybe there's a whole segment of matter humans are unfamiliar with which interacts very little with the matter we know about but interacts with itself in complicated ways. Maybe there are dark matter solar systems populated by dark matter people who are just as confused as we are about the weird gravitational anomalies caused by our otherwise invisible existence. Communicating through gravity would certainly be an interesting challenge! I don't really believe this, but my point is basically the same as Hamlet's: "There are more things in heaven and earth than are dreamt of in your philosophy"--that is, it's arrogant to expect humans to be in a position to observe all the parts of the universe. Perhaps some things are just hidden.
Another recent post of mine in this vein is a summary of particle classifications.
I agree this is off-topic, but I really like WPF. It has a steep learning curve and a lot of quirks, but data binding, templates, and the layout system save a lot of time and make things look nice. The people complaining about WPF in your link often called themselves old; maybe that's the real problem (I'm quite young).
I actually spent a few seconds trying to rework the punchline to get around that little inconvenience, but no dice. I'm sure Feynman thought the same thing and I'm pretty sure he was smarter than I am (certainly he was quicker), but he apparently wasn't able to get around it either.
I read evidence for an argument once that concluded smart people exhibit non-standard behavior of all kinds. Unfortunately I didn't get to read their reasoning, though I do remember two of their examples: night owls and homosexuals. My college dorm had a ridiculously high percentage of both, and everyone there would have been at the uppermost end on general population intelligence tests, so the conclusion is at least consistent with my personal anecdotal evidence. Non-right-handedness among your company's IT workers might be caused by the same underlying mechanism. I'm probably best described as cross-dominant myself: I write with my left hand, use forks alone with my right, use knife+fork with either, use the mouse with either, use right to masterbate, throw right-handed, and have finer motor control over my left.
but without demonstrating it to be true and to what degree I cannot see how any meaningful conclusions can be drawn.
Well, if the model predicts reality accurately, one concludes the premises are plausible or likely. It's not the greatest form of evidence, but it's enough for many purposes. I've seen physicists ignore the lack of mathematical rigor in their arguments, and as far as I can tell the justification is the same: the results are pretty good, so the steps taken must have been correct.
Haha, thank you. Just to be clear, my original post left off where Feynman did, before CP violation was discovered.
YouTube'ing Feynman is a great way to spend some free time. I wish we had videos of some of the other great minds in history--what I wouldn't give to watch Gauss say, "here's how I did it"!
According to this study,
Homosexual men had 82% greater odds of being non–right-handed than heterosexual men
I guess we learn to use both at once ;)
if you ever meet a perfect version of yourself constructed by aliens from radio transmissions, don't shake their hand.
For those who don't know, this refers to a story in the Feynman Lectures on Physics. Here's my version; I've taken some liberties.
Imagine you're on the phone with an alien who speaks English, except they don't know what "left" and "right" mean. You want to explain it to them so they know which tentacle they should use to shake the right-handed President's hand if they should ever meet. The alien can be anywhere in the universe, so you can't refer to stellar positions or similar, leading you to devise an experiment for them to perform.
Your initial attempts use gravity, electricity, and magnets, but you notice each experiment comes out essentially the same if you swap "right" and "left"--for instance, you could give the alien instructions for making a clock in hopes of defining "right" using clockwise rotation, except if the alien made the clock exactly backwards by reversing the notion of "left" and "right", they wouldn't be able to tell. A particle physicist happens by and tells you about a magical experiment involving the weak nuclear force that *does* distinguish left and right inasmuch as the experiment fails if the alien screws up "right" and "left" and succeeds otherwise. (For the curious, some more details here and here.) Great, problem solved.
"But wait!" the physicist says. "The alien needs to use regular matter instead of antimatter in the experiment. The results will be reversed otherwise! Come to think of it, I have no idea how to tell them the difference between matter and antimatter. If you ever meet them and they start trying to shake your left hand, RUN, since the alien will be made of antimatter!"
This discussion made me wonder where the new particle falls in standard particle classifications. I've always been curious so I finally looked it up. My notes are below if anyone else is curious. I abbreviated the fundamental forces as (G)ravity, (E)lectromagnetic, (W)eak, (S)trong.
(1) Elementary particles: indivisible (probably). Includes fundamental fermions and bosons.
(A) Fundamental fermions: obey Pauli exclusion principle and Fermi-Dirac statistics. Includes quarks and leptons.
(I) Quarks: six flavors; combine in groups of two or three; interacts with GEWS. The "S" allows atomic nuclei to exist.
(II) Leptons: six types, three charged, three not.
(a) Charged leptons: mostly, the electron. Interacts with GEW. The "E" there makes chemistry work.
(b) Uncharged leptons: neutrinos. Interacts with GW, so not much with ordinary matter.
(B) Fundamental bosons: obey Bose-Einstein statistics, disobey Pauli exclusion principle. Includes gauge bosons, Higgs boson, and gluons.
(I) Gauge bosons: force carrying particles. Photons carry E, W- and Z-bosons carry W, gluons carry S.
(II) Higgs boson: would explain the non-masslessness of some fundamental particles. Currently the only unobserved standard model particle.
(III) Graviton: would carry G. Theoretical status somewhat uncertain; not a standard model particle; currently unobserved.
(2) Composite particles: composed of multiple elementary particles. Includes hadrons, atoms, molecules.
(A) Hadrons: two or three quarks held together by S. Includes baryons and mesons.
(I) Baryons: fermions made of three quarks. Most famous examples are protons and neutrons. Huge variety--~hundreds or more depending on how you count.
(II) Mesons: bosons made of two quarks. All unstable. Huge variety--~hundreds or more depending on how you count..
Note that each particle has an anti-particle, where each composite particle's anti-particle is obtained by replacing the constituent elementary particles with corresponding anti-particles.
The \Xi_b^{*0} particle (the summary left off the 0 for some reason...) is a baryon, so it falls under (2AI) in the above list. In light of the variety of the hadrons and their composite particle nature, this story isn't terribly exciting (at least to me).
[Please correct any mistakes; I'm not a physicist.]
It hurt bad when Stampede Linux was no more.
Was it like, say... getting run over by a herd of your favorite quadruped?
This! Him skipping this vote make me put him firmly in the 'fuck this guy' pile.
Wow, I'm impressed. If you take that much care in all your decision making, in Ron Paul's shoes I would certainly be honored to have your vote for president!!1
The vote was moved up a day unexpectedly and all the "not voting" people combined wouldn't have changed the outcome. You could at least withhold judgement until knowing his side of the story; perhaps he was campaigning and planned to return for Friday's vote, I dunno (and I'm nearly certain you don't either). But no, nevermind, let's rush to judgement--Fuck RON PAUL! Gah, you even complain about your own past judgement-rushing in the same post you rush to judgement again.
I'd like to note Paul did not vote "Present" (which means you're not added to the Yea or Nay tally but were around for the official vote). Maybe he does deserve scorn for not voting against it, but I don't have enough info to say, and as far as I can tell neither does anyone here.
The bit of my post you quoted has nothing to do with your comments, which in turn have little to do with my post. I'm sorry, but did you even read it? My post is not about FTL communication whatsoever. It's about traveling between distant planets in a single human lifetime using the known relativistic effect of length contraction.
Does that mean we'll encounter life from other planets? Perhaps not. That depends on whether any forms of FTL ever prove feasible, beyond which there's the roll of the dice of the rarity of planets with life.
People always seem to forget (or never learned) length contraction. If you're in a spaceship pointed at the center of the galaxy, as you approach the speed of light the length between you and the center of the galaxy contracts. The contraction factor (the Lorenz factor, I'll call it g) is determined by your speed. It's 1 when you're at rest compared to the center of the galaxy and goes to infinity as you approach the speed of light. To give some actual numbers, if you want to travel 30,000 (rest frame) lightyears in 1 year, you'd need a speed of about 0.99999999945c and a Lorenz factor of about g=30021.
Mass dilates as well, meaning that an object at this speed has more kinetic energy than the classical KE = 1/2 mv^2 formula. The special relativistic formula giving the energy required to bring a mass m at rest to a speed encoded in the Lorenz factor g is mc^2 (g-1). At the above speed, g-1 = 30020, so you would need to convert 30020 times as much mass as your spacecraft has to energy in order to get to the required speed. For comparison, for a 100 metric ton spacecraft this is around 0.7 times as much energy as the sun puts out each second.
Actually doing this is certainly impossible today and for the near future, but perhaps one day it will be feasible to send small crafts between worlds. It's important to note that, for the people 30,000 light years away, your journey would take approximately 30,000 years. But to you it would take only 1 year. If you made a return trip, Earth would be more than 60,000 years different. The point is that you could make the journey in a single human lifetime, with an efficient enough propulsion system, so long as you were alright with both earth and your destination experiencing a large passage of time.
It gets really unintuitive if you go to the rational numbers which are dense.
Actually I disagree. There is a simple way to visualize the countability of the rationals, which is a variation on the following (I believe standard) enumeration that I won't formalize: ...
1/2
1/3, 2/3
1/4, 2/4, 3/4
1/5, 2/5, 3/5, 4/5
I realize numbers are repeated but it's simple conceptually to cut out the duplicates and, if you want, to repeat the process in each interval [n, n+1]. The picture corresponding to the version I've written is of course equally spaced points with ever finer spacing, and for any rational number with a given denominator that number will be hit at that denominator's stage.
By "unintuitive" I meant that, for finite sets, proper subsets are smaller in the sense above, whereas infinite sets do not possess this familiar property. Of course it's subjective :).
And of course once you are there, with a dense set of numbers, it is completely unintuitive that you can still put numbers "in between". And even more numbers than you already have.
Hmm... sorry, I again disagree. Rational numbers have repeating decimal expansions; if this fact is intuitive (I believe it is, though a rigorous proof may not be), then picking a number that doesn't have a repeating decimal expansion (easy to do) means you've picked an irrational, so there are numbers "between" the rationals. I would at least find it quite weird if the set of infinite binary strings and the set of finite binary strings had the same cardinality--I would very much want to know the injection. Since I find the converse of Cantor's conclusion unintuitive, I find Cantor's conclusion intuitive. Again, though, the phrase is subjective.