Cordial Deconstruction

Observations from our shared single objective reality in a materialistic, naturalistic, & macro-deterministic universe.

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Reply to a Comment on My Schrödinger’s Cat Post

Posted by Karl Withakay on May 1, 2011

Commenter your wrong left the following comment to my Deconstruction post on Flash Forward’s mishandling of the Schrödinger’s Cat thought experiment:

“Ok, you seem to have completely missed the point here. The point of Schrodinger’s cat is precisely about quantum probability, which you have stated, and you seem to have a knowledge of this thought experiment and what it means. The thing that is really getting to me is the fact that the point is still being made in almost exactly the same way, but you are quibbling over the fact that it is not explained fully and mentioned the radioactive isotopes and the Copenhagen interpretation. Surely a 10 minute conversation about this thought experiment would waste time in the programme and really doesn’t matter. The nitty gritty stuff is for scientists, not for people just watching some action on television. Don’t get me wrong I love reading physics as much as any studious person, but it really doesn’t matter in the slightest that he didn’t go into every single little detail regarding the experiment. Stop wasting your time complaining and read more physics, you’re obviously interested in it. Not only that but you’ve wasted my time having to correct your ignorance.”

What follows is my reply to that comment, which I felt was worthy of it’s own post.

It would appear to be you who has completely missed the point and demonstrated your ignorance on the topic.  By substituting a poisoned sardine for the decay of a radioactive isotope, quantum probability has been eliminated from the thought experiment and has been replaced by a regular non-quantum, deterministic event.

Further, when the physicist states that the observer gets to choose whether the cat is alive or dead, that is not quantum physics and the collapse of the quantum waveform, it’s a philosophy of a post modernist subjective reality, dependant on the perception and will of the observer.  In quantum mechanics, the observation of the cat in the original thought experiment collapses the quantum waveform and solidifies the current state of the cat; it does not choose which state the cat is in, which is what the physicist in the TV show said.

The writers completely misunderstood the thought experiment, and got it wrong on two key points.  They replaced a quantum probability with a deterministic event, and then gave the observer a choice in the end state of the cat rather than the observation only being a choice to create the end state of the cat with no ability to choose what that end state was.

It is acceptable to boil a scientific concept like quantum probability and decoherence down to a form the average TV viewer can understand, but only if it remains relatively accurate in the key points.

I have not wasted my time at all, and if you have wasted you time is not my fault.  It would seem that I have either read more physics than you, or I have at least better understood and appreciated the nuances of what I have read.  It also seems that you either failed to pay attention while reading my post, or you were unable to understand they key points of my post.   If by reading this reply you better understand the key points as to why the writers got the thought experiment wrong, then you have not wasted your time at all either.

And by the way, you’ve spelled your name wrong if your intention was to say “you’re wrong” rather than talk about a wrong that I posses.  I normally don’t quibble about simple spelling mistakes, but I would think if someone takes the time to compose a 181 word statement claiming someone  is wrong on a matter of quantum physics, that they would take time to make sure they haven’t confused “your” with “you’re”.  Such a mistake hardly adds to your credibility.

Your comment has been Cordially Deconstructed.

Posted in Critical Thinking, Criticism, Flash Forward, Followup, Science, Television, This Blog | Tagged: , , , , | Leave a Comment »

No Reason to Fear Aliens (Again)

Posted by Karl Withakay on January 11, 2011

Recently I came across an article on space.com, Study: If We’re Not Alone, We Should Fear the Aliens by Mike Wall, SPACE.com Editor, that I thought was deserving of some Cordial Deconstruction.  Technically, this is more a Deconstruction of the study the article was reporting on, and not so much of the space.com article, though I may refer to the two interchangeably in this post.

The article makes the following statement which it describes as the only two possibilities based on the study:

“When considering the prospect of alien life, humankind should prepare for the worst, according to a new study: Either we’re alone, or any aliens out there are acquisitive and resource-hungry, just like us.”

My basic reaction to this false dichotomy is, 1.) Bull and 2.) So What?

I’ll first deal with the assertion that we are probably alone.  It would only take one other example of a planet with intelligent life in the approximately 300 sextillion (30 X 10,000 billion billion) stars in the visible universe for this assertion to be wrong.  The fact that we have not heard from ET is not reasonable support for the assertion that not even one  single ET existst. There are numerous possible reasons why we might not have heard from ET yet, other than ET doesn’t exist (though that is a possibility).  Among those possible reasons are the following:

-It’s possible ET’s civilization didn’t stay at the level where they leaked radio signals into space long enough.  (Fiber optics, directed digital broadcasts,  and beyond anyone?)

-It’s possible that ET is so far away that there hasn’t been enough time for its signals to reach us yet.

-It’s possible that ET’s civilization is too far away for their leaked signals to be discernable from background noise.

-It’s possible that ET evolved on a planet that wasn’t conducive to developing technology.  Maybe the requirements for life are there, but there aren’t enough heavy metals to develop technology beyond the Stone Age level.  Maybe the environment is so hostile that ET is just barely able to survive and doesn’t have time to develop beyond the Stone Age.  Maybe it’s a water world of whale like creatures.  (Our whales haven’t developed radio technology despite a lack of serious interference from humans until a  few hundred years ago.)

Really, at this point the only conclusion that we can come to from the fact that we have not yet detected ET is that if ET exists, it is not an easy thing to detect ET.

As a footnote, I’ll mention that there are at least two other possible reasons why we may not have heard from ET:

-It’s possible that ET died out before developing radio technology, either due to natural events or self destruction.

-It’s possible ET’s civilization didn’t last long enough to be detected.

Though both would support the idea that we are currently alone, they lead to another possibility- Even if we do detect signals from an extraterrestrial intelligence, considering that they will have likely originated a very long time ago (anywhere from thousands to billions of years ago), ET may have died out since transmitting the signals, and thus we could technically currently still be alone despite the signal.  In the absence of an actual visit by ETs, we can’t actually know if there are currently any other intelligent civilizations light years away.  Even with a visit from ET, they can’t know if their civilization still exists back on their home world, signals and information can’t travel faster than the speed of light.

One very astonishing assertion by the article/study is that evolution is predictable, and that it inevitably leads to intelligent civilizations.

“Further, Conway Morris says, evolution operates predictably, producing relatively predictable outcomes. These two suppositions argue that alien life, if it exists, should be fairly similar to terrestrial life, generating intelligent beings much like us”

It’s very astonishing because life existed on this planet for about 3.7 billion years before a species came along that could fashion simple stone tools, let alone broadcast electromagnetic signals such as radio.  For 99.9% of the time that there has been life on this planet, there has been no species that comes close to the study authors’ definition of intelligent.  Multicellular didn’t appear on Earth until after about 2 billion years after life first developed, and vertebrates took about 3.2 billion years to show up.  Dinosaurs roamed the Earth fat, dumb, and happy for about 160 million years and may have stayed that way if they hadn’t been killed out in a mass extinction.  Seeing as we have only one example of a planet with life on it to use as a reference, I think it’s incredibly anthropic and near sighted to conclude intelligent beings are always the inevitable result of evolution.

The article quotes Conway Morris, one of the authors of the study, regarding the ability to contact alien civilization despite the probable vast distance between them,

“At least so far as this galaxy is concerned, a distance of circa 100,000 light years doesn’t seem insurmountable, given a relatively slow diffusion rate and a geometrical rate of establishment of colonies,”

Ignoring the possibility that intelligent life could be as rare as one civilization per galaxy (we really have no idea how rare or common intelligent life may be outside the sailor system) as Morris does, that’s an interesting use of the word “given”.  Normally, I would reserve the word given in such a context for either an established fact or a reasonable assertion.  In this context the word would be better replaced with the word “assuming”.  There is no reason to assume a geometrical rate of establishment of colonies or any interstellar colonies at all.  I’ve previously shown in a series of posts that there’s no point in worrying about an alien invasion, partly because the resource requirements of interstellar travel make such travel and alien invasion highly impractical.  Simply put, the energy and resource requirements for interstellar travel vastly outweigh any possible returns.  If you have the resources to travel to another star to plunder one of its planet’s resources, you don’t need to do so.  By analogy, why drive from Florida to Alaska to buy gas for your car?  If you have enough gas to drive to Alaska, you don’t need to go.  The numbers don’t add up.  This concept is covered more in depth in posts on the linked page.

The other reason to not worry about an alien takeover is that, assuming I’m wrong, we’re doomed anyway, as I also concluded in a post in the above link.  If ET is so advanced and capable that it can travel across the stars (perhaps superluminally) without bankrupting their planetary economy, then they will find us and do as they please no matter how hard we try to hide or prepare, and our puny bullets and nuclear weapons likely won’t bother them at all.

Don’t worry, be happy, because worrying won’t matter one way or another.  :)

 

Series of related posts HERE.

Posted in Critical Thinking, Criticism, Science, Space | Leave a Comment »

Bill O’Reilly Throws Muslims Under the Bus

Posted by Karl Withakay on October 14, 2010

I believe Bill O’Reilly believes in what he says.  When he recently said, “Muslims killed us on 9/11“, I believe that he believes that we were attacked by the Muslim religion itself  (ie: we were attacked by the Muslims) rather than just that the persons who carried out the attack were Muslims.

I also believe he is dead wrong.  Though it is technically correct to say that 9-11 was carried out by Muslims, it is also technically correct to say 9-11 was carried out by heterosexual men.  In either of these cases, the statements serve no useful purpose and only serve to deceive and mislead by making false implications and encouraging erroneous inferences about responsibility for the attacks.  As a heterosexual man who did not participate in the attacks, I wish not to be incorrectly associated with those that did, and I imagine many Muslims feel the same way.

I could provide various statements about  things that were done by (people who happened to be) Republicans or Christians that I’m sure Bill O’Reilly would freak out about if you said them to his face, but I think I’ve already made my point.

Posted in Critical Thinking, Criticism, Media | Tagged: | Leave a Comment »

Astronomer (Probably) Has 99% Chance of Being Wrong

Posted by Karl Withakay on September 30, 2010

Astronomers have spotted a so-called Goldilocks planet ( Gliese 581g)orbiting another star.  A goldilocks planet is a one that is of the right size to be terrestrial and which lies in the habitable zone of its parent star; conditions which are needed to support life remotely close to as we know it.

During a press briefing, astronomer Steven Vogt, professor of astronomy and astrophysics at the University of California, Santa Cruz said the following:

“Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say, my own personal feeling is that the chances of life on this planet are 100 percent,”

“I have almost no doubt about it.”

This is an astounding statement for any reasonable scientist to make, even one that is an astronomer and not a biologist.  I would even say such a statement borders on irresponsible, assuming there isn’t some missing context or qualification to that statement.  Professor Vogt is essentially saying that the fℓ term (the fraction of the habitable worlds that actually go on to develop life at some point) from the Drake Equation is 100%, which is extraordinarily unlikely to be true.

Whether or not already developed life flourishes everywhere we look on earth is independent from the likelihood of it developing in the first place.   By analogy (admittedly one of the weakest forms of argument), diesel fuel is very hard to light on fire, but burns very well once started.

We really don’t have any reasonable estimate for the fℓ term of the Drake Equation, but I think we can say is significantly less than 100%.  If it were 100%, you would expect life to be spontaneously developing all the time.  You would expect to be able to observe spontaneous abiogenesis at least under laboratory conditions, and yet, we have not yet ever observed life arising from non-life, therefore it must be somewhat less than common.

Additionally, this planet may be the most habitable world we’ve found so far, but the Garden of Eden it ain’t.  First of all, it orbits a red dwarf star, which isn’t ideal.  Red dwarf stars are fairly deficient in UV radiation which is probably important to, and may be vital for, the development and evolution of life.  Also, the planet is tidally locked with its parent star, meaning one side of the planet is always facing the star and one side is always in darkness- not ideal for moderate temperatures on most of the planet.  It’s likely the planet itself would have a Goldilocks zone of its own; the day side is probably too hot, the night side is probably too cold, and the zone bordering the day and night zones is probably the habitable zone of the planet.

Even if my last paragraph regarding the actual habitability of the world in question is totally wrong, even if this planet existed in exactly the same conditions as the Earth in regards to parent star, orbit, composition, magnetic field, etc, there’s just no reason to assume a 100% chance of life.  By definition, that would mean life had to instantaneously spring up the moment habitable conditions were achieved, and that life would continue to spontaneously arise all the time.  I personally believe (without much supporting evidence) that the odds of life developing in any ideal environment are probably very low, but I will confidently say the odds are significantly less than 100%, and they are less for Gliese 581 g than they were and are for Earth.

Posted in Critical Thinking, Criticism, Science, Space | Tagged: , , | 1 Comment »

Reply to a Comment on Interstellar Travel

Posted by Karl Withakay on August 22, 2010

Someone going by the handle of Speising made a comment on my post Follow-Up: Energy Requirements of Interstellar Travel, and the reply I composed grew so large that I decided to make it into a full post.

The comment was:

“So what about ram-jet like ships? probably quite useless (to vulnerable) as carriers for an invasion force, but they do not have the problem of carrying all that fuel with them.
also, of course, If we assume ET doesn’t want to spend 200 or more years making a round trip to Earth… doesn’t necessarily apply for ET’s with, eg., longer life spans than ours.”

Thanks, for the comment, speising.  Basically, you’re talking about a Bussard Ram Jet.  There’s a few problems associated with that.

You’d be scooping up hydrogen to use as a fusion fuel, but hydrogen’s not a particularly good fuel for fusion, believe it or not.  The proton-proton chain, which is the primary source of energy production in stars less than 1.3 solar masses, is a very slow process (like an average of one billion years per reaction in the first step), which is a good thing otherwise the sun would have burned out after just a few million years.

You could theoretically use the CNO cycle for hydrogen fusion, but the confinement and cooling requirements would likely be insurmountable.  We’re talking about temperatures and densities greater than that of the core of the sun.

Also, the interstellar medium isn’t as dense with hydrogen as Bussard thought it was, and you probably wouldn’t be able to scoop up enough fuel.

All this completely ignores the shielding requirements, which I never even went into in my earlier posts, mostly because I concluded interstellar travel was already impractical before even getting to the shielding requirements.  Traveling at speeds even at one tenth the speed of light, every particle of dust floating in space is going to impact your space craft with a lot of kinetic energy.

Let’s assume a particle of cosmic dust floating in interstellar space with zero velocity relative to the Earth.  Let’s also assume this particle is medium sized cosmic dust, say 300 micrometers in diameter, and let’s further assume it’s density is average for cosmic dust, 2.0 g/cm^3.  This particle has a mass of only 2.82X10-8 kg or .028mg.   If our vessel is traveling at 1/10th the speed of light relative to Earth, that particle of cosmic dust is going to impact our spacecraft with a kinetic energy of 12 Megajoules.  To put that into perspective, lets assume a typical automobile mass of 1500kg (3300lb); that particle of dust is going to impact our spacecraft with the same kinetic energy as a car traveling at 454km/h (284mph).  How are you going to protect against that kind of collision, and what do you do if you run into a particle that was 10 or 100 time larger?  300 micrometers is pretty small; a strand of human hair is 100 micrometers wide.

In regards to the other part of your comment,

“If we assume ET doesn’t want to spend 200 or more years making a round trip to Earth… doesn’t necessarily apply for ET’s with, eg., longer life spans than ours.”

I’ll just add that even if an alien species were to have a significantly longer life span that humans, it wouldn’t necessarily follow that their perception of the passage time or their value of time were different than ours.  If science found a way to extend you lifespan to 1000 years, would you be interested in spending 200 years in a submarine without port if there was an alien planet at the end of the trip?  I think 200+  years is still a long time, no matter how many years you have ahead of you in life.

Posted in Critical Thinking, Followup, Science, Skepticism, Space, This Blog | Tagged: , | Leave a Comment »

My Take on the Dawkins Interview at TAM8

Posted by Karl Withakay on July 13, 2010

This past weekend I has the pleasure of attending The Amazing Meeting 8 in Las Vegas with my friend Polite Scott.  It was, of course, amazing.  The keynote speaker was famed British evolutionary biologist, ethologist, and author Richard Dawkins.  Instead of giving a keynote address, Dawkins was interviewed Bob Costas style by JREF president D.J. Grothe.  While I kind of missed a formal keynote address, I enjoyed the interview very much.  I always enjoyed the casual, intimate interview format of Later with Bob Costas; it allowed for a more personal interview, and this interview was very similar.

Although there was much of interest in the interview, sometimes it’s the little things that leave the biggest impact.  My friend Polite Scott, for instance, tweeted the following after the interview:

Enjoyed Richard Dawkins’ session at TAM8, but was even more impressed to learn @DJGrothe is a comic book fan #TAM8

The thing that really caught my attention was Dawkins’ use of personal pronouns for non-specific, gender neutral references.  Depending on how you look at it, the English language is either gender biased or at least gender specific.  In German, for instance, the word sie can mean she, they, or even you (singular or plural), but in English, gender in pronouns implies actual gender.  Consider the following sentence:

Talk to your doctor about what he would choose for his family.

Fifty years ago, if you were addressing a crowd of people, this is how you would have phrased that statement without giving it a second thought, and it wouldn’t have even been seemed that gender biased since most people’s doctors would have been men.  Indeed, most people would still phrase it that way without a second thought.  Since the sexual revolution, there have been a couple of different alternative ways of dealing with gender when using pronouns in non-specific contexts.  One way is to use both masculine and feminine pronouns at the same time as in:

Ask your doctor what he/she would choose for his/her family.

It’s certainly inclusive, but it’s terribly awkward.  Another common choice is to use plural pronouns for non-specific references as in the following:

Ask you doctor what they would choose for their family.

This has always seemed to me to be the more elegant solution, but I admit I have had a hard time following it, mostly due to the influence of my tyrannical high school English teacher who insisted on using masculine pronouns for non-specific references.  (He was and older, conservative teacher at a conservative Lutheran high school )

Dawkins’ interview demonstrated a third option that had never previously occurred to me.  When he used pronouns for non-specific references, Dawkins used feminine pronouns.  He would have phrased the example phrase thusly:

Ask your doctor what she would choose for her family.

At the same time, this phraseology is both inclusive in its own way and thought provoking.   Every time he used a feminine pronoun for a non-specific reference, it made me think of how women might feel when people use masculine pronouns instead.  If you’re an English speaking, Christian, white male in the United States, you might not realize or care how non-inclusive our language and society can be.  On the other hand, sometimes I wonder if this is one of the reasons behind the various English only attitudes in this country.  Maybe some people realize how non-inclusive our country can be, and they don’t want to end up with the short straw at some time in the future.  Maybe they don’t see how it can be any other way other than society being focused on one particular language and culture, and they want to make sure it’s their culture that dominates.

This past weekend in Las Vegas, one man gave a hint to an admittedly receptive (fairly liberal) audience of approximately 1,300 people that maybe it doesn’t always have to be that way.  Think about it the next time you use a pronoun in a non-specific context.

Posted in Critical Thinking, English Language, Inclusivity, Richard Dawkins, TAM, The Amazing Meeting, Thoughtful/Random Observation | Tagged: , , , , , , | Leave a Comment »

Sci-Fi Science and Skepticism Fail on Syfy

Posted by Karl Withakay on June 10, 2010

A couple of months ago, I was flipping through channels on my POOP TV* and caught a few minutes of one of those really bad, direct to cable movies they run all the time on the Syfy channel.  The movie was Savage Planet and before I changed the channel, I chanced to hear the following lines of dialog spoken by one of the characters in the movie:

“I always believed there had to be a scientific explanation for everything.  Science was the only answer.  Since I’ve been here, I’m rapidly becoming a skeptic.”

I hit the record button on my DVR remote so I could preserve that line of dialog for a potential future blog post.  However, I didn’t continue watching the program, and I stopped the recording after the dialog, so I only have a few minutes recorded.

I don’t really know what the character was specifically talking about, but I imagine it had something to do with the killer space bears the reviews say the movie contains.  Regardless, this quote is an epic fail on the part of the writers of the movie.  They apparently buy into the philosophy that “science doesn’t know everything”, which is really a misunderstanding of science, since science is a process, and not a body of knowledge or answers.

To quote the Wikipedia article on science,

“Science is a systematic enterprise of gathering knowledge about the world and organizing and condensing that knowledge into testable laws and theories.”

Science is not the answer, it is the means to an answer; it is they way to provide the explanation.  If it is beyond  your ability to explain scientifically, that is not a failure of science; that is a failure of your ability and knowledge base.  Lacking a scientific explanation for a phenomenon does not make that phenomenon supernatural or paranormal, it simply means you haven’t found the scientific explanation yet.  It can be very frustrating to not have the answer for something.  It can be even more frustrating to know that the answer to that question may never be discovered during your lifetime, but that is no reason to engage in a god of the gaps fallacy and invent some supernatural explanation just so you can have an answer.

The dialog is also a profound misunderstanding of skepticism and the skeptical community.  While the word skepticism can technically mean any questioning attitude, skepticism is about challenging claims lacking empirical evidence.  It is also about challenging and examining the evidence that is used to support a claim.  Skepticism is a crucible for inquiry in which claims are subjected to the fires of scientific scrutiny to burn away the extraneous fluff, leaving only scientific knowledge and/or more questions to be answered.

I don’t really expect any better for a low budget sci-fi movie that likely went straight to Syfy, but I wanted to blog about it because I’ve heard the “Science doesn’t have all the answers” gambit many times before, and I wanted to give my take on why that concept is so wrong.

*POOP TV:  Picture Out Of Picture.  I have a 40” HDTV sitting next to my 60” HDTV.  When I was researching buying a new 60” HDTV, I wanted to get a model with PIP (Picture In Picture) because my then current TV had it, and it was pretty nifty for watching one football game while keeping track of another.  I discovered that it would cost a lot more extra to get any of the current models with PIP, more than the cost of buying a second, smaller HDTV.  So I bought a budget model 32” LCD TV to go next to my new 60” model.  I found that I liked the setup not just for watching two football games at the same time, but also for watching TV while playing video games, especially when I am just performing some boring, repetitive action to level up a character, exploit a flaw in the game to generate endless amounts of money, or get some achievement.  I liked the POOP TV setup so much that a couple years later, I sold my 32” TV to a friend and upgraded the POOP TV to a 40” model.

I have no wife or kids, I have to spend my money on something, right?

Posted in Critical Thinking, Criticism, Quotes, Sci-Fi, Science, Skepticism, Space, Syfy, Television, Thoughtful/Random Observation | Leave a Comment »

Final Follow-Up on the Probability of an Alien Invasion

Posted by Karl Withakay on June 3, 2010

This post is part 3 of my Deconstruction of Stephen Hawking’s comments about contact with alien intelligences being risky.  Part one was a general overview of why alien visitation/invasion is highly unlikely.  Part two involved some rough numbers regarding the energy requirements for interstellar space travel at the near light speed velocities required to get anywhere in a remotely reasonable time frame.

In this post I will address the hypothetical “what if” scenario where some advanced alien intelligence has made a fundamental advance/ breakthrough in physics and engineering that allows interstellar or even intergalactic travel at effective speeds far in excess of the speed of light at a relatively low energy cost.

So, what if it is possible?  What if the laws of physics as we know them need to be rewritten or at least get greatly expanded, and it turns out it is possible to travel interstellar distances in practical time frames instead of decades, centuries, or longer?  Further, what if it is possible to do so with a relatively low energy cost instead of needing energy equivalent to tens of thousands of thermonuclear weapons or the yearly outputs of thousands of nuclear reactors?

Well, in short, in that case we’re probably screwed, and there’s still no reason to worry about it because there’s nothing we can do about it anyway.

Any alien civilization that advanced would probably be so far beyond us technologically that we probably couldn’t hope to resist their invasion or even evade detection by them.  We’ve been making radio transmissions for well over 100 years, and during that time, our transmissions have been leaking into space to worlds more than 100 light years distant.  I think it’s reasonable to speculate that any civilization capable of effectively superluminal travel is likely to have an equally advanced ability to detect and locate other intelligent civilizations or suitable worlds.  If such a super advanced civilization is out there, and they are bent on conquest, they probably already have thousands or even millions of probes scattered throughout the galaxy looking for worlds to plunder in addition to their super advanced observation/ search techniques they will be using from their home world.  Basically, if they are reasonably capable of getting here, they are probably capable of finding us whether we want them to or not.

Certainly, if they are capable of getting here, there can be little question of their ability to conquer us with little difficulty, as long as they’re not to worried about our welfare.  Some might point to US and Soviet difficulties in Vietnam, Afghanistan, and Iraq as reasons to think we could have some hope of resisting a technologically superior invader, but I would disagree.  First of all, the difference in technology would be closer to trying to fend off A-10’s with paper airplanes, the Ethiopians fighting off the Italian Army in 1935, or the Aboriginal Americans fighting off European invaders, settlers, or colonists.  The Soviets did pretty well in Afghanistan until we started supplying the other side with modern military equipment.  Our problems in Vietnam have been well documented and much debated, but I think it’s at least safe to say we weren’t engaged in an unrestricted attempt to eliminate North Vietnam’s military capability, and they had some help from the Soviets to boot.  Likewise, we’re not attempting to eliminate the populations of either Afghanistan or Iraq.  I’m pretty sure we could do that if we wanted to and we didn’t care about preserving the infrastructure.  Independence Day may have been a fun movie, but it was delusional in regards to our ability to fight off an alien invasion.  We very probably have little chance against a super advanced alien invasion force unless we can find some equally advanced alien allies or a fifth column to help us.

Additionally, Stephen Hawking seems to be implying that if we just stay silent, ET may not find us.  This super advanced ET probably doesn’t need our help to find us.  Irrespective of all the radio transmissions we’ve been leaking into space for over a hundred years, ET would probably be able to detect our rich blue and green world on their own without our help.  We are already are able to detect planets only a few times more massive than the Earth orbiting other stars and detect elemental composition of stars with what would be extremely primitive techniques and technologies compare to what any superluminal civilization would have at its disposal.  It seems likely that ET would be able to find our rich, garden world whether we were here to transmit to them or not.

In summary:  If extraterrestrial aliens have the ability to get here in a reasonably short period of time without bankrupting their planetary economy, then they can probably find us, come here, and kick our butts if they want to.

Frankly, the fact that we haven’t yet been conquered by ET is a hint that maybe either ET isn’t interested in or capable of coming here and conquering us.

Posted in Critical Thinking, Criticism, Followup, Science, Skepticism, Space, Stephen Hawking | 3 Comments »

Follow-Up: Energy Requirements of Interstellar Travel

Posted by Karl Withakay on May 2, 2010

This is a follow-up to my recent post, Cordial Deconstruction of Stephen Hawking? (Am I So Bold?) where I discussed the likelihood that an alien intelligence would bother crossing the universe or galaxy to plunder the resources of the planter Earth.

In this post, I will discuss the energy requirements of interstellar travel.  Before I begin, I want to explain that I’m not going to show the math involved in the numbers, both because many people won’t be interested in the equations, and because this post is going to be long enough without showing all the calculations and equations involved.  I’ve also ignored the time dilation factor which would reduce the relative travel time of the journey for the passengers of a spacecraft traveling close to the speed of light, but it only makes a significant difference at speeds that are energetically prohibitive anyway.

First, a discussion of the distances involved when discussing interstellar travel.  To quote Douglas Adams’ Hitchhiker’s Guide to the Universe,

“Space is big. You just won’t believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it’s a long way down the road to the drug store, but that’s just peanuts to space.”

A typical galaxy is about 30,000 light years in diameter, the Milky Way being about 100,000 light years across.  The distances between galaxies is even more mind bogglingly huge; the typical distance between galaxies is about 3 million light years.  The visible universe is about 93 billion light years in diameter.  (This is the current, commoving distance, not the distance at the time the light from the furthest visible stars was emitted.)  So, to start, lets rule out intergalactic travel and focus on interstellar travel from within the Milky Way galaxy to see how practical that would be.

The nearest star to the sun is Proxima Centauri at a distance of about 4.2 light years, but Proxima Centauri is not a great candidate for habitual planets, for several reason.  It’s a red dwarf, and that could pose numerous problems.  It’s also variable, which almost closes the door on Proxima Centauri as a candidate for our hostile ET to come from.  Moving on, there are 64 known stars within about 16 light years of the Earth, so let’s just say ET is coming from our back yard, say 10 light years away, though the aliens probably wouldn’t be so local unless life is very common in the universe.

So let’s look at how much energy it would take ET to get here from an unspecified plant 10 light years away.  If we assume ET doesn’t want to spend 200 or more years making a round trip to Earth, they’re going to need to travel fast, really fast.  Even 10% of the speed of light isn’t going to cut it.  Let’s shoot for 90% of the speed of light (c).  At .90 c, it’s going to take about 11 years to make the trip from ET world to earth, if ET can accelerate and decelerate nearly instantaneously.

So now we have our target speed, but we need to know the mass of ET’s vehicle.  An object the size of the space shuttle (~110,000 kg for the orbiter by itself or around 2,000,000 kg for the whole system with boosters and fuel) seems a little physically small for an 11 year journey, so let’s try something a little bigger.  A Virginia class submarine is about 8,000,000 kg and is a craft designed for long term endurance travel; let’s assume ET’s craft is the same mass.

The amount of energy needed to accelerate an object of a mass of 8,000,000kg to.90 c is 7.45 9.32 * 10^23 Joules, which is about 180 million megatons of energy.  This is the equivalent of 3.6 ~4.5 million Tsar Bombas, the most powerful nuclear weapon ever detonated.  It would take more than four five million kg of antimatter annihilating with the same amount of matter to produce this much energy.  It’s worse than it looks, because the ETs need to slow down to a relative stop when  they get here, which will take the same amount of energy as the acceleration, so we’re talking about 360 ~450 million megatons of energy just  for a one way trip.  But it’s even worse than that.  We are ignoring the mass of the energy source and any propellant used in for ET’s spacecraft, and we are assuming 100% efficiency in the conversion of the energy source into vehicle velocity, which isn’t going to happen in the real universe.  All things considered, without going into the increasingly complicated math (which would require us to start using calculus since the mass of the vehicle now decreases as we consume reactant & propellant), we probably need to increase our estimate of the energy requirements by an order of magnitude or so.

So, bottom line, at the end of our rudimentary estimate of the energy requirements to travel at .90 c, we’re talking about an energy requirement in the order of a billion megatons or so.

OK, what if ET is a little more patient and is willing to endure a 200 year round trip at .10 c?  The energy requirements drop to ~17,000 ~870,000 Megatons of energy (or 17,000 Tsar Bombas) for a one way trip. (It’s not a linear decrease because we’re talking relativistic mechanics here.)

(For reference, doing a little math, I calculate the Callaway Nuclear Generating Station in Missouri generates about 8 megatons of energy a year.)

So, in summary, the energy requirements are massive for velocities even 10% of the speed of light, and absurdly huge for speeds 90% of c, and even at those speeds, we are limited to about 10 light years of distance for any reasonable length journey.  Why would any ET, no matter how conquest driven they were, bother expending such energy resources to plunder the resources of another world, assuming they could even find a suitable planet to plunder in their local stellar neighborhood?

I think we can sleep soundly at night, never having to worry about Stephen Hawking’s ETs ever attacking the Earth ID4 style.

In regards to the energy requirements of some mythological faster than light propulsion system, who can really say what those would be?  I can speculate that they would be much greater than those of traveling at velocities at “significant” percentages of the speed of light, and someone else can say that as long as we are speculating about faster than light travel, why can’t we speculate about some relatively low energy process to achieve those speeds?  It’s all wild speculation if not outright fantasy at that point, so there’s really no numbers to talk about.

Posted in Critical Thinking, Criticism, Followup, Science, Skepticism, Space, Stephen Hawking | 12 Comments »

Cordial Deconstruction of Stephen Hawking? (Am I So Bold?)

Posted by Karl Withakay on April 26, 2010

Would you drive to Alaska to buy gasoline?  Stephen Hawking seems to think you might if your local gas station ran out.

Here’s my take on the ID4/ hostile aliens thing:

(And here is where I dare to Cordially Deconstruct the position of someone who is much, much, much smarter than I am)

There’s something on the order of 100 billion galaxies in the known universe, and there’s something on the order of 100 billion stars in each of those galaxies.  We’re just beginning to scratch the surface of figuring out how many of those stars might contain planets and how many of those planets or their moons might be remotely habitable by life as we know it.  I think it would be wise to assume that some forms of extremophiles could survive on worlds more hostile than what we conservatively call habitable.  And although we don’t really have any reasonable clue for estimating the probability of life arising on a suitable world, let alone the odds of intelligent life developing, 10,000 billion, billion stars is a lot of stars (10^20), and that’s a lot of spins on the roulette wheel of life to hit the jackpot only once.  In the absence of actual data, it seems reasonable to speculate that there’s life elsewhere in the universe, and some of it is probably more advanced than we are.

That being said, it also seems likely to me that inter-galactic space travel isn’t particularly likely, and we don’t have to worry about whether ET is friendly or not.

You may think this is modern arrogance, but despite mysteries like dark energy and dark matter, we have a pretty good idea of how the universe works, and it looks like the universal speed limit (can not obtain) for things with mass is the speed of light.  The practical effect of this limit is that inter-galactic travel would take an incredibly long time to get anywhere not in you own star system.  Intergalactic travel would also take an impractically large amount of energy if you wanted to travel at any velocity approaching a significant percentage of the speed of light.  Even if we speculate the discovery of some way to travel faster than the speed of light, it seems reasonable to also speculate it would extremely (prohibitively) energy intensive.

So what might we have here in an ultra-advanced, space faring, alien species?  We have ETs that have no motivation to travel to other stars for anything other than esoteric knowledge gathering that probably won’t be of any use to the folks back home anyway, since they’ll likely all be long dead by the time the explorers got back.  Listen, if you have the energy resources to travel across the galaxy (either at sub-light or superluminal velocity), you don’t need to plunder the resources of other worlds; you’ve got resources coming out of your ying tang, and you’ve got the technology to do whatever you need  with those resources.  You’d be better off just terraforming some reletively nearby world rather than traveling across the galaxy to plunder a distant Earth-like planet.

Traveling across the galaxy to plunder the Earth’s resources would be like me driving to Alaska from Missouri to buy gas if my local filling station ran out.  Why bother if I already have the resources to get there?

5-2-10:  See the followup post here:  Followup: Energy Requirements of Interstellar Travel

Posted in Critical Thinking, Criticism, Science, Skepticism, Space, Stephen Hawking | 6 Comments »

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