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If you have the genomes of your parents, and your own genome, yours is about 70 new spot mutations, about 60 crossovers, and you have to specify who your parents were. About 600 bytes of new information per person. You could store the genomes of the entire human race on a couple terabytes if you knew the family trees well enough. I tried to nail down the statistics for that in http://burtleburtle.net/bob/future/geninfo.html .

true random one time pads are made from random noise (radioactive decay, random thermal noise in electronics, ....) that noone else would have access to. The problem is then shipping it over to the destination.

you are talking about psudo-one-time-pads, using a seeded PRNG. The main problem with most PRNG is that they have a small key and once you have watched a small amount of the output (guessed a small amount of the encripted text) you can predict the rest.

I have come across several PRNG that have a relatively simple implementation, but which have a large enough key space and repeat time that any sort of probabilistic attack is not feasible. (see ISAAC : http://www.burtleburtle.net/bob/rand/isaacafa.html ) - it has a key space of over 10^2000 (the number of atoms in the universe times the number of milliseconds the universe is likely to be in existence is about 10^100). The only known attack requires access to many megabytes of output from the generator, and means you only need to check the sqrt of the number of keys (10^1000 keys). baring a mathematical breakthrough there is essentially no chance of messages encrypted with ISAAC generated one time pads this side of the heat death of the universe without the key being given to the person doing the decrypting.

could you explain how the magnetic flux of a permanent magnet retains the same strength over time

The gravitational attraction of a given mass of matter also remains constant over time (proton decay notwithstanding), but I would also ridicule any PMM based on known gravitational forces.

Keeping an open mind does not preclude rejecting extraordinary claims (unless there is correspondingly extraordinary evidence, which is clearly lacking here).

Be careful what you dismiss as pseudoscience

Good advice indeed -- but given that the inventor claims something that has never been demonstrated in a reliable or repeatable way, and has huge reams of both experimental and theoretical evidence against it, and has furthermore been repeatedly used in hoaxes and frauds over the years...

May I suggest easily-google-able sites detailing the unworkability of PMM's in general, and electromagnetically-based ones in particular:

http://www.phact.org/e/z/freewire.htm
http://en.wikipedia.org/wiki/Perpetual_motion_mach ine
http://www.lhup.edu/~dsimanek/museum/unwork.htm
http://www.kilty.com/pmotion.htm
http://www.phact.org/e/dennis4.html
http://burtleburtle.net/bob/physics/whythere.html
http://commons.bcit.ca/physics/rjw/pmm/text/em_pmm s.htm

Great scientific pseudoachievements / pseudoadvances:

Phlogiston (a THEORY!! WOOO!)
http://www.jimloy.com/physics/phlogstn.htm

Montgolfier gas
http://www.chm.bris.ac.uk/webprojects2003/hetherin gton/final/montgolfier_bros.html

LSD as a mind control drug
http://www.mindcontrolforums.com/lsd-mc-cia.htm
(to be differentiated from drug addiction, which is certainly controlling)

Frontal lobotomies
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd= Retrieve&db=PubMed&list_uids=6379496&dopt=Abstract

Perpetual motion
http://burtleburtle.net/bob/physics/whythere.html

the 4^H5^H3 kingdom classification of organisms
http://encarta.msn.com/media_461530646/Classificat ion_of_Organisms.html

There should be no difference between MD4 and MD5. If you have found one you probably should write a paper about and submit it to the crypto cummunity.

I say use a fast hash instead. You don't need crypto security for dir hashes. Waste of CPU.

See
http://burtleburtle.net/bob/hash/evahash.html
for a reasonably fast hash func. Heck you could probably even use adler32.

A computer can produce art, but a computer cannot be an artist (at least for humans, yet). Art is something for its audience to appreciate. An artist has to understand what the audience will appreciate, then find something that will be appreciated. Computers have to be told what an audience will appreciate. However, computers can be fanastic at finding something that an audience will appreciate once they're told exactly what to look for.

Here, I wrote a Java applet for gravitational simulations, wrote another program to produce a bunch of parameters, and fed the simulator the parameters. I think the result is art, because the audience (me) appreciates it. The computer did most of the work (both writing the parameters and doing the simulation). But I'm the artist, because I'm the one who decided I appreciate it.

I'm thinking of buying a 1200 sq ft house in an established area, tearing it down, and building a 6000 sq ft house in its place. Most of that square footage would be underground, but still. I'd have flat roofs for decks or gardens or water heating on top, not really to be green, but just because with a 60'x90' lot and a 50'x60' house, where else would I put the back yard? Trial floor plans here. I'd tear down an old house and build a new because there are no vacant lots left in Silicon Valley.

My current 1400 sq ft townhouse (3 adults 3 small children, really 900 sq ft you can walk on) is cramped. People sleep in the living room. There's more stuff than storage. There's no space for a workshop or a kid-free home office. Reading a newspaper is challenging. I can imagine moving into an 800 sq ft house, but I'd probably have to give up my computer and guitar to do it.

What's the disadvantage to having a large house other than heating? Making houses tiny is a much more intrusive way to address heating costs than using insulation, solar water heating, and glazed windows.

There is such a thing as a perfect hash ...

Anything you can test with a command line, do. Text in, text out, use 'diff result.log official.log' to find if you broke anything. Anything that requires a mouse, though, I hear there's products for that but I've never used them.

I have a pet project (jenny) that generates testcases for cross-functional testing, where the number of testcases grows with the log of the number of interacting features rather than exponentially. It often allows you to do a couple dozen testcases instead of thousands, and it lets you cover more interactions too. It's of no use for pull-down menu interfaces, though, where the goal is pretty much to test every node in the tree and there's no interactions between nodes.

And this is a dupe from 4 years ago.

Earth's Second Moon 2nd Moon Orbiting Earth Discovered

Time to plug my free pairwise testing tool jenny (it jennyrates tests). 10 on/off dimensions with three constraints (-w1a2b3a -w1a3b5a -w1a5b9a) took 8 or 9 testcases, depending on the seed to the random number generator.

Pairwise testing takes fewer testcases than Taguchi's orthogonal arrays. Orthogonal arrays guarantee every that every dimension setting appears an equal number of times (does it guarantee that for pairs of dimension settings too?) N-way testing just requires that every combination of n settings is covered at least once. Detecting bugs only requires n-way testing, where n is 2 or 3.

I saw something similar from the BBC when they linked to one of my pages last September.

Cruithne

Sounds like they've discovered a Kemplerer Rosette. :)

This shouldn't be too hard (at least it doesn't look too hard sitting here on a Sunday morning, half way through my first cup of liquid brains). The key is to note that we can't (and therefore needn't bother trying to) enforce the topology at all times. Instead, we just want to bias the network towards the desired form. For example:

New nodes pick a random twenty+ bit ID. This would probably not be enough to prevent collisions, (cf the Birthday Paradox) but that can be dealt with presently. New nodes connect up to whoever then can find. This would be pretty much what happens on most p2p now. Once the node has the desired number of connections, it can rank them by comparing the number of bits its ID has in common with the IDs of each peer (the Hamming Distance between the IDs). As further peers are discovered, it can establish connections to any that are Hamming-closer than its worst ranked peer and drop the worst ranked peers from its connections. Likewise, if a node detects a pair of peers that are Hamming-closer to each other than either is to it, it can "introduce" them to each other. If two peers meet and discover they have the same randomly chosen ID, the younger can flip one bit (for each ID bit, count the number of ctive connections that differ on that bit; flip one with the max count) and continue. Fat pipe peers can run more than one ID if they wish (cf UltraPeers)

-- MarkusQ

Bingo. We can support billions of times the population of earth right in our own solar system. Terraforming planets is a waste of time.

I've been building simulators of Dyson swarms in recent days.

But tomorrow we just might have a (sigh) Beowulf cluster of machines that could brute force a 256 length key in a matter of hours.

This would argue otherwise.

I know nobody asked me, here's my two cents. (BTW, isn't this instant worldwide publication stuff great?)

This is how IP law should work for software.

1. If I write it from scratch then I can do what I want with it.
2. If I write it from scratch then you can't sell it without my permission.
3. I'm allowed to write it from scratch.

It turns out that software isn't as nonobvious as it seems. For example, the incredibly nonobvious orbit-integration algorithms I found in 2000 were exactly the same as the ones someone else found in 1990, and those were the same as ones someone else found in the 1973. This is the norm. It's happened to me over and over and over again.

Software patents should not exist. Authors should start with all rights to their code. Software patents claim that authors have no rights to their code if their code reinvents something that a previous author patented. It is extremely common for code to reinvent things that have been coded (and patented) before. Therefore software patents should not exist.

I'm working on a distributed index. That is, the index itself is distributed. It's harder to take down the index than the data being indexed. I have a spec. The index nodes are lists in HTML pages.

According to this article, I'd be a contributory but not vicarious infringer. I might be exempt because it's a generic data structure, not specially suited to any type of data over any other. In fact it's better at static data than quickly-disappearing contraband.

My main question: are there other distributed index projects going on? If there are, I've reinvented the wheel enough times already, thank you.

I threw together a proposal for this, calling them Booga Trees.

The basics are:

1. Everyone sharing a file needs to store at least one leaf of the tree
2. When you store a leaf of the tree you also have to store all the nodes in the path from the root to the leaf. This means there are an exponential number of copies of the higher nodes.
3. The standard format of a node is an XML fragment, and is also an HTML list. So these things can be built and navigated by hand immediately, as well as by new search software later.

Exact key lookup takes O(logN) time to look through O(logN) sites when there are N sites. Maintenance is O(logN) per path-to-leaf too. There's no central point of failure, in fact having half the network go down has little effect beyond the leaves in that part of the network being inaccessible.