The interesting argument, related to theories known for a century (Galon-Watson,Fisher) are correct for single genes, or completely linked clusters (e.g.mitochondria, Y chromosome). It does not hold in the presence of recombination.
In other words, the conclusion is false for entire individuals, but true for single genes or very tightly linked clusters.
As someone who has thought about this seriously, I basically agree with much of what you said, but it needs clarification. A basic reference is "Darwin's Dangerous Idea", by Daniel Dennett, and his basic slogan is "Cranes but no skyhooks".
One basic idea is that hereditary variation occurs on many different time scales simultaneously, e.g. cutlural (mimetic), epigenetic (DNA methylation), as well as regular DNA mutations which themselves fall into several classes each with a different frequency of occurrence ( simple sequence DNA, duplications, point mutations). My own thinking is that this non-uniformity of time scales of hereditary variation, when viewed in retrospect, can appear pseudo-Lamarkian, i.e. locally goal directed.
This multiple time scale search is a known strategy of search in certain genetic algorithms, and in some circumstances speeds up the search considerably. So in some sense one could regard Darwinian evolution itself as a process of distributed design (Dennett), with the pseudo-Lamarkian "goals" and different time scales of search partially giving the retrospective appearance of intelligence.
Whence we reconcile the major apparent discrepancy between darwinian evolution and "intelligent design" (as it would be understood by a rational person).
Not so many realize this, so I'm glad to meet you.
The reviewer and posters are sort of missing the point, here, which is that if you inject about *2 grams equivalent for a human* i.e. 20 mg/kg of starch coated rust (dextran coated iron oxide) intravenously into a mouse, or presumably a person, you can see where it preferentially leaks out of microscopic blood vessels in areas of inflammation (here inflammation in the pancreatic islets due to autoimmune diabetes) by MRI (changes in the spin relaxation time). Now that's a hack, to my mind way better than many others.
The entire pdf of the original article is available free on Biomed Central. Incidentally, resolution is not too important here, so this should work for "low field MRI", which uses ordinary magnets (.01-.1 Tesla), and costs about 10%
of ordinary MRI (exclusive of technician and radiologist fees), i.e. a real currently existing "tricorder"
I got a phishing attack today.
They ask me to log in to
https://www.paypal.com/
Note the extra s.
Non-obviously, it's fake.
How does this redirection work?
For a slightly different take on what to look for see http://slashdot.org/comments.pl?sid=148007&cid=124 03702
Like any other experiment, one is exploring a parameter space, some experiments explore more of the parameter space than others, different experiments different parts. Your objections say that there are significant portions of the parameter space missing from the "fiduciary 4-volume" of the proposed experiment. My comments said the same. Still, its an experiment, and might as well be done as well as possible.
Whether or not one expects it, this is an experiment, and is probably worth doing, given the
miniscule cost. Theory may say "no go", but theory here is very weak
Thank you for your brilliant idea for an experimental test
of the hypothesis that one of a certain number of forms of
time travel will be invented in our future light cone, in
the form of the "first" time travellers convention.
I have a suggested improvement to your experiment.
As Marvin Minsky has
estimated, the smallest form with a level of mental
complexity similar or greater than our own (representing say
10^15 bits of information changing at 10^12 bits/second would
be about (10^4 nm)^3 or (10 micron)^3, i.e. about the size of
a single cell. The time travel vehicle would presumably be a
little larger.
Furthermore, as he has suggested it might be very much energetically advantageous
to send a much smaller vehicle and passenger back. Finally,
hundreds to thousands of years in the future of human beings,
the optimal size of humans may be engineered to be much, much,
smaller in any case as one of only a few possible solutions to
the malthusian problem of overpopulation, and the second order
problem of loneliness (see
http://anotherview.memebot.com/ ) for a little more on this.
Therefore, the coordinates of your convention are insufficiently
precise, for the most likely attendees. Rather, the "convention
center" should be scaled for attendees of various sizes
Therefore, I propose the following modification of your experiment:
1. place (at least) a light microscope in your convention hall
2. advertise the (4-local) spacetime coordinates of its specimen
stage widely, but make the precision and accuracy of these coordinates relative to the size
of the entity coming to visit, e.g. for organisms of size 1-3
meters,
the resolution of coordinates you have given seem to be fine.
For smaller organisms/entities advertise more precise coordinates.
This sounds like a nice, clean experiment. However, wasn't this effect first reported 50 years ago in photon antibunching and the Hanbury-Brown Twiss effects? These are some of the most subtle and beautiful effects in modern physics.
I think Radio Shack sells something like an 8MB
PDA for $30. Maybe we could hack something like this, e.g. keyboard, USB, built in modem, etc.
Alternatively,, what is happening to all the older laptops?
I don't understand. I thought freecache took care of this, if I took care of the content and permissions, and it was archived material (not real time).
Wouldn't it be simpler for the system to approximately assign a language to any commment. Then allow readers to filter threads by language, similar to search engines. The poster could also help out if necessary. This shouldn't cost much computationally.
Doing a google search on "ocean renewable power", suggests that the total practically extractable energy from all forms of power is much less than 5% of what will be required in the next 50 years (25 terawatts). See
http://online.itp.ucsb.edu/online/colloq/lewis1/ oh/03.html and its parent pages and online video for details
Re:The bigger picture -updated version
on
Out of Gas
·
· Score: 1
This is a potentially serious consideration, technically known as the "energy payback time" but for solar the numbers are not so bad. For example, the energy payback time of silicon solar cells today is 2-4 years, but for the nanocrystalline cells I was referring to is apparently only 3 months.
See
http://www.nanosolar.com/advantages.htm [nanosolar.com] as recommended above.
For wind power a google search on "energy payback time" suggests less than 6 months
Re:Umm Ethanol
on
Out of Gas
·
· Score: 3, Informative
Many experts agree that biofuels have negative thermodynamic efficiencies, i.e. consume more energy in aggregate than they produce.
Biological photosynthesis has a net thermodynamic efficiency of 0.3% = 3E(-3). Compare this to 10-30% efficiency for photovoltaic.
There is the possibility of direct solar photochemical reduction of CO2 to methanol say, which could be very efficient, but this is only in early stages in the lab now, and is expected to take several decades to develop. However it may be close to what you require.
In the meantime solar (any form) is the only technology which has the right scale (unlike wind and hydro, more than 1-2% of total energy requirements are extractable), is relatively safe, and is close to being practical soon.
The bigger picture -updated version
on
Out of Gas
·
· Score: 4, Informative
There is a very clear online recent lecture on this topic by Nathan Lewis, a chem professor at Caltech who is active in this field. It is titled "The Future of Power and Energy in the World"
You can find it with many slides at http://online.itp.ucsb.edu/online/colloq/lewis1/
The summary is roughly that we need to make photovoltaics about 10 fold cheaper than they are today(about $4/watt ->$.40/watt), on the way to making them as as cheap as housepaint (say $.20/watt). There is no theoretical obstacle to doing this, and several promising lines of research. If (really when) we can do this ($.20/watt), solar electric energy will be cheap enough to electrolytically reduce CO2 to methanol (CH3OH) which is a fine fuel for transportation, etc., and is already nicely interfaced to out current energy distribution and use systems.
At this low cost, we can even pull CO2 out of the atmosphere directly, directly reversing the CO2 greenhouse effect (my own addition).
Furthermore, this is by far the best option, e.g. otherwise we would need 5000 new 1GW fission reactors to supply the growth in energy needs contemplated in the next 50 years (construction of 2/wk for 50 yrs.) This seems much too dangerous.
Since this is the best apparent practical way out, since we are really talking about a major determinant of the fate of the earth, and timing is critical, one might wonder why the federal funding is so low (about $10M/yr in the US maybe).
Some of the recent research, and the progress made by startup companies is summarized at
http://www.konarkatech.com/news_articles-forbes_ no v.php
Has anyone actually used this for an extended period of time? How does it actually scale for different sorts of volume?
For example, I would like to moderate and host various (probably realvideo) compressed lectures as a public service. Some would be academic in content, such as is seen at http://www.msri.org/publications/video/index.html or http://online.kitp.ucsb.edu/online/ ; others might be more political, or science policy. I would not expect more that a few thousand hits/year for most of them, but some might get popular. A typical hour lecture might run 25Mb.
Is this a necessary or desirable service for this purpose? What about for a high school geometry course, say?
There is a very clear online recent lecture on this topic by Nathan Lewis, a chem professor at Caltech who is active in this field.
It is titled "The Future of Power and Energy in the World"
You an find it with many slides at
http://online.itp.ucsb.edu/online/colloq/lewis1/
The summary is roughly that we need to make photovoltaics about 10 fold cheaper than they are today(about $4/watt ->$.40/watt), on the way to making them as as cheap as housepaint. There is no theoretical obstacle to doing this, and several promising lines of research.
If (really when) we can do this ($.40/watt), solar electric energy will be cheap enough to electrolytically reduce CO2 to methanol (CH3OH) which is a fine fuel for transportation, etc., and is already nicely interfaced to out current energy distribution and use systems. At this low cost, we can even pull CO2 out of the atmosphere directly, directly reversing the CO2 greenhouse effect.
Furthermore, this is by far the best option, e.g. 5000 new fission reactors would be needed to supply the growth in energy needs contemplated in the next 50 years (construction of 2/wk for 50 yrs.) This seems much too dangerous.
Since this is the best apparent practical way out, since we are really talking about a major determinant of the fate of the earth, and timing is critical, one might wonder why the funding is so low (about $10M/yr in the US maybe).
The pictures on Iwo Jima were just as stated and shown above, but they were not reinacted, according to the photographer who took them. This is all now very well researched. There was another (fourth) picture of the platoon taken at the same time, on the same roll, with everyone facing the camera, which was obviously posed, and more "formal". Later, there was confusion when the photographer was asked whether some of the pictures were posed, and he replied yes, thinking of this other "formal" picture. The famous photo was an unrehearsed, unreinacted, replacement of the original flag with a larger one.
Slashdot Mirror
Maybe separate exams, to be given by proctors, either with the course or at the time of hire. IBM used to do this.
In other words, the conclusion is false for entire individuals, but true for single genes or very tightly linked clusters.
Questions?
As someone who has thought about this seriously, I basically agree with much of what you said, but it needs clarification. A basic reference is "Darwin's Dangerous Idea", by Daniel Dennett, and his basic slogan is "Cranes but no skyhooks".
One basic idea is that hereditary variation occurs on many different time scales simultaneously, e.g. cutlural (mimetic), epigenetic (DNA methylation), as well as regular DNA mutations which themselves fall into several classes each with a different frequency of occurrence ( simple sequence DNA, duplications, point mutations). My own thinking is that this non-uniformity of time scales of hereditary variation, when viewed in retrospect, can appear pseudo-Lamarkian, i.e. locally goal directed.
This multiple time scale search is a known strategy of search in certain genetic algorithms, and in some circumstances speeds up the search considerably. So in some sense one could regard Darwinian evolution itself as a process of distributed design (Dennett), with the pseudo-Lamarkian "goals" and different time scales of search partially giving the retrospective appearance of intelligence.
Whence we reconcile the major apparent discrepancy between darwinian evolution and "intelligent design" (as it would be understood by a rational person).
Not so many realize this, so I'm glad to meet you.
The reviewer and posters are sort of missing the point, here, which is that if you inject about *2 grams equivalent for a human* i.e. 20 mg/kg of starch coated rust (dextran coated iron oxide) intravenously into a mouse, or presumably a person, you can see where it preferentially leaks out of microscopic blood vessels in areas of inflammation (here inflammation in the pancreatic islets due to autoimmune diabetes) by MRI (changes in the spin relaxation time).
Now that's a hack, to my mind way better than many others.
The entire pdf of the original article is available free on Biomed Central. Incidentally, resolution is not too important here, so this should work for "low field MRI", which uses ordinary magnets (.01-.1 Tesla), and costs about 10% of ordinary MRI (exclusive of technician and radiologist fees), i.e. a real currently existing "tricorder"
I got a phishing attack today. They ask me to log in to https://www.paypal.com/ Note the extra s. Non-obviously, it's fake. How does this redirection work?
Whatever happened to ammonia liquid-gas phase heat pipes? Doesn't the phase transition beat mere convection?
For a slightly different take on what to look for see http://slashdot.org/comments.pl?sid=148007&cid=124 03702
Like any other experiment, one is exploring a parameter space, some experiments explore more of the parameter space than others, different experiments different parts. Your objections say that there are significant portions of the parameter space missing from the "fiduciary 4-volume" of the proposed experiment. My comments said the same. Still, its an experiment, and might as well be done as well as possible.
Whether or not one expects it, this is an experiment, and is probably worth doing, given the miniscule cost. Theory may say "no go", but theory here is very weak
Thank you for your brilliant idea for an experimental test of the hypothesis that one of a certain number of forms of time travel will be invented in our future light cone, in the form of the "first" time travellers convention.
I have a suggested improvement to your experiment.
As Marvin Minsky has estimated, the smallest form with a level of mental complexity similar or greater than our own (representing say 10^15 bits of information changing at 10^12 bits/second would be about (10^4 nm)^3 or (10 micron)^3, i.e. about the size of a single cell. The time travel vehicle would presumably be a little larger.
Furthermore, as he has suggested it might be very much energetically advantageous to send a much smaller vehicle and passenger back. Finally, hundreds to thousands of years in the future of human beings, the optimal size of humans may be engineered to be much, much, smaller in any case as one of only a few possible solutions to the malthusian problem of overpopulation, and the second order problem of loneliness (see http://anotherview.memebot.com/ ) for a little more on this.
Therefore, the coordinates of your convention are insufficiently precise, for the most likely attendees. Rather, the "convention center" should be scaled for attendees of various sizes Therefore, I propose the following modification of your experiment: 1. place (at least) a light microscope in your convention hall 2. advertise the (4-local) spacetime coordinates of its specimen stage widely, but make the precision and accuracy of these coordinates relative to the size of the entity coming to visit, e.g. for organisms of size 1-3 meters, the resolution of coordinates you have given seem to be fine. For smaller organisms/entities advertise more precise coordinates.
Regards,
Seth Goldberg
What about appending "+" before the word? Maybe this is not so redundant.
This sounds like a nice, clean experiment. However, wasn't this effect first reported 50 years ago in photon antibunching and the Hanbury-Brown Twiss effects? These are some of the most subtle and beautiful effects in modern physics.
I think Radio Shack sells something like an 8MB PDA for $30. Maybe we could hack something like this, e.g. keyboard, USB, built in modem, etc. Alternatively,, what is happening to all the older laptops?
I don't understand. I thought freecache took care of this, if I took care of the content and permissions, and it was archived material (not real time).
Wouldn't it be simpler for the system to approximately assign a language to any commment.
Then allow readers to filter threads by language, similar to search engines.
The poster could also help out if necessary. This shouldn't cost much computationally.
This prompted me to check why the phenomenon.
Flints today are apparently made of Cerium Mischmetal.
See here for details.
Any chemists out there?
Doing a google search on "ocean renewable power", suggests that the total practically extractable energy from all forms of power is much less than 5% of what will be required in the next 50 years (25 terawatts).
/ oh /03.html
See
http://online.itp.ucsb.edu/online/colloq/lewis1
and its parent pages and online video for details
This is a potentially serious consideration, technically known as the "energy payback time" but for solar the numbers are not so bad. For example, the energy payback time of silicon solar cells today is 2-4 years, but for the nanocrystalline cells I was referring to is apparently only 3 months. See http://www.nanosolar.com/advantages.htm [nanosolar.com] as recommended above.
For wind power a google search on "energy payback time" suggests less than 6 months
Many experts agree that biofuels have negative thermodynamic efficiencies, i.e. consume more energy in aggregate than they produce.
Biological photosynthesis has a net thermodynamic efficiency of 0.3% = 3E(-3). Compare this to 10-30% efficiency for photovoltaic.
There is the possibility of direct solar photochemical reduction of CO2 to methanol say, which could be very efficient, but this is only in early stages in the lab now, and is expected to take several decades to develop. However it may be close to what you require.
In the meantime solar (any form) is the only technology which has the right scale (unlike wind and hydro, more than 1-2% of total energy requirements are extractable), is relatively safe, and is close to being practical soon.
There is a very clear online recent lecture on this topic by Nathan Lewis, a chem professor at Caltech who is active in this field. It is titled "The Future of Power and Energy in the World"
_ no v.php
s -h ybPV.php
t 13 55h.htm
You can find it with many slides at http://online.itp.ucsb.edu/online/colloq/lewis1/
The summary is roughly that we need to make photovoltaics about 10 fold cheaper than they are today(about $4/watt ->$.40/watt), on the way to making them as as cheap as housepaint (say $.20/watt). There is no theoretical obstacle to doing this, and several promising lines of research. If (really when) we can do this ($.20/watt), solar electric energy will be cheap enough to electrolytically reduce CO2 to methanol (CH3OH) which is a fine fuel for transportation, etc., and is already nicely interfaced to out current energy distribution and use systems.
At this low cost, we can even pull CO2 out of the atmosphere directly, directly reversing the CO2 greenhouse effect (my own addition).
Furthermore, this is by far the best option, e.g. otherwise we would need 5000 new 1GW fission reactors to supply the growth in energy needs contemplated in the next 50 years (construction of 2/wk for 50 yrs.) This seems much too dangerous.
Since this is the best apparent practical way out, since we are really talking about a major determinant of the fate of the earth, and timing is critical, one might wonder why the federal funding is so low (about $10M/yr in the US maybe).
Some of the recent research, and the progress made by startup companies is summarized at
http://www.konarkatech.com/news_articles-forbes
http://www.konarkatech.com/news_articles-solrac
http://www.st.com/stonline/press/news/year2003/
http://www.nanosolar.com/advantages.htm
(this is an updated version of a previous post)
.
Has anyone actually used this for an extended period of time? How does it actually scale for different sorts of volume?
For example, I would like to moderate and host various (probably realvideo) compressed lectures as a public service. Some would be academic in content, such as is seen at http://www.msri.org/publications/video/index.html or http://online.kitp.ucsb.edu/online/ ; others might be more political, or science policy. I would not expect more that a few thousand hits/year for most of them, but some might get popular. A typical hour lecture might run 25Mb.
Is this a necessary or desirable service for this purpose? What about for a high school geometry course, say?
There is a very clear online recent lecture on this topic by Nathan Lewis, a chem professor at Caltech who is active in this field. It is titled "The Future of Power and Energy in the World" You an find it with many slides at http://online.itp.ucsb.edu/online/colloq/lewis1/ The summary is roughly that we need to make photovoltaics about 10 fold cheaper than they are today(about $4/watt ->$.40/watt), on the way to making them as as cheap as housepaint. There is no theoretical obstacle to doing this, and several promising lines of research. If (really when) we can do this ($.40/watt), solar electric energy will be cheap enough to electrolytically reduce CO2 to methanol (CH3OH) which is a fine fuel for transportation, etc., and is already nicely interfaced to out current energy distribution and use systems. At this low cost, we can even pull CO2 out of the atmosphere directly, directly reversing the CO2 greenhouse effect. Furthermore, this is by far the best option, e.g. 5000 new fission reactors would be needed to supply the growth in energy needs contemplated in the next 50 years (construction of 2/wk for 50 yrs.) This seems much too dangerous. Since this is the best apparent practical way out, since we are really talking about a major determinant of the fate of the earth, and timing is critical, one might wonder why the funding is so low (about $10M/yr in the US maybe).
The pictures on Iwo Jima were just as stated and shown above, but they were not reinacted, according to the photographer who took them. This is all now very well researched. There was another (fourth) picture of the platoon taken at the same time, on the same roll, with everyone facing the camera, which was obviously posed, and more "formal". Later, there was confusion when the photographer was asked whether some of the pictures were posed, and he replied yes, thinking of this other "formal" picture. The famous photo was an unrehearsed, unreinacted, replacement of the original flag with a larger one.