search results matching tag: AB

» channel: learn

go advanced with your query
Search took 0.000 seconds

    Videos (86)     Sift Talk (7)     Blogs (5)     Comments (448)   

A Marine and his Dog

Honda Fit Rolls 7 times - caught on dash camera

braschlosan says...

I CALL SHENANIGANS! These are prone to heavy understeer.
I am going to guess he had the front sway bar disconnected or a 25mm rear sway bar installed with high tire pressures in the rear and possibly had the ABS disabled. The stability control may be crap but in stock form a professional driver probably couldnt do this if he TRIED.

Trailer for documentary about Calvin & Hobbes

Analog digital clock

Can you believe in both science and religion?

shagen454 says...

What is religion anyway? Many of them exude the same principles of which I believe have some truth in all of them. Hinduism and Buddhism probably moreso than others but that is just me and what I have seen and learned.

Though there is definitely more verifiable truth to Math and Science. We were built and evolved in this intergalactic system, a system largely devoted to geometry... and an intergalactic system that we do not know much about.

We hardly even know how our brain functions and even less about the subconscious or what happens when we sleep, we know these aspects of our own being impact us, we can study the brain waves, we can hypnotize, we can slip in different molecules into our serotonin receptors, but we still do not understand why. It is a mystery yet to be solved. Much like this phenomenon we might believe as God. Eventually, I believe that we can figure out the science and it will be mindbogglingly simple creating much complexity. Akin to a simple formula as x=abs(x) or y=abs(y) or m=x*x+y*y or x=x/m+cx or y=y/m+cy. But, math will not contain the science of all of the states of being, spirit realms, and matter that do not relate to us on Earth. In my opinion this is only one life. The science of the next could be completely different.

Is God a deity or a they? The programmers of a gigantic reaction that occurs probably in many more places than we can imagine. Who are connected to everything. Maybe, it was a blob of energy that never knew it could create consciousness and the Earth evolved us to be conscious to protect it. Yeah, great job guys.

No one has that great of an idea because if it is real, it would be absolutely mind blowing and beyond all human comprehension, yet probably very simple once we understood it. There is only one way I know to reach out and touch a little bit of it on Earth and it is absolutely amazing and terrifying all at the same time and beyond human linguistics. Science so far is hardly trying to figure it out but it is science, because if all living things ingest this molecule that resides in everything and then is able to see through dimensional portals, into afterlife, through the universe, think it is dead because it is impossible otherwise... well that is Spirit Science something of which is only beginning to come to fruition.

I just think everyone is somewhat right, even Christianity, hehe, as long as they are teaching compassion and love; there is something to it be it group therapeutic, psychological, or really there is something much bigger going on that science has no way of quantifying. Again, I am not saying anyone is right or wrong but that there are truths in everything and to completely disregard them might not be the best approach, even if it is an amalgamation of prior knowledge so very twisted by imperialists throughout these two thousand plus years.

Science is what we need to get behind to begin unraveling these mysteries, even though it is a slow process. I bet that science will eventually grapple to learn that these mystical underpinnings of religions, cults and ancient sacraments... these things Christians call holy light, prayer, God, resurrection, afterlife, angels... fit into the coding of the universe. If string theory and quantum mechanics did not already open that can of worms up. But, I also doubt that whoever created this thing that we are, wants to be seen and would have put up many barriers, knowing full well that its creations would seek them or it out. Or maybe it is the exact opposite....

radx (Member Profile)

Ice Cream "Indigogo" campaign

A Day in India

Bowser Wants Guns: Guns don't kill – Mario does.

Volvo Trucks - Emergency braking at its best!

Kitty Playing Dead and High Five

U.S. Students Graduating Without Object Permanence Skills

Timelapse-icus Maximus 2012 ~ A Burning Man for Ants

Numberphile - The Fatal Flaw of the Enigma Code Machine

radx says...

Edit: Oh boy, wall of text crits for 10k.

His explanation was rather short and somewhat misleading. Maybe they thought a proper explanation would have been too dry or too lengthy to be of any interest for a sufficient number of their viewers.

tl:dr

If all rotor settings are indicated to be correct, a feedback loop within the circuit indicated a subset of correct connections on the plugboard, even if the initially assumed connection turned out to be wrong. It didn't show all connections, but enough to run it through a modified Enigma to determine if it's a false positive or in fact the correct setting. If it was correct, the rest could be done by hand.

----------------------- Long version -----------------------

Apologies in advance. We had to recreate parts of the Bombe as a simulation, but a) it's been a while and b) it was in German. I'll try to explain the concept behind it, hopefully without screwing it up entirely.

The combination of clear message and code snippet (2:25) is called a crib. This can be used to create a graph, wherein letters are the vertices and connections together with their numerical positions are the edges.

For example, at position 1, "A" corresponds to "W". So you'd create an edge between "A" and "W" and mark that edge as "1". At position 4, "B" corresponds to "T", so there's the edge marked as "4". All edges are bidirectional, the transformation at a specific position can go either way.

Once your graph is finished, you check for loops. These are essential. Without loops, you're boned. In this case, one loop can be found at positions 2,3,5 in form of "T->E->Q->T".

Here the Bombe comes into play. It uses scramblers, each combining all three rotors plus reflector of an enigma into one segment. This way, one Enigma setting is functionally equal to a single scrambler.

Now you can use those scramblers to create an electrical circuit that corresponds to your graph -- scrambler = edge. All scramblers are set to the same initial configuration. The first scramber remains at in the inital configuration, while the second and third get configurations in relation to their edge's numerical value. Configuration in this case means the value of their internal three rotors, so there are 26*26*26 possible settings within each scrambler.

It's basically a sequence of three encryptions.

Example: in our little TEQ triangle, the first scrambler (TE, 2) gets a random starting position. The second scrambler (QE, 5) gets turned three notches, the third scrambler (QT, 3) gets turned one notch. The initial configuration might be wrong, but only the relation between the scramblers matters. A wrong result simply tells you to turn all scramblers another notch, until you get it right.

You have a possibly correct setting when the output matches the input. Specifically, a voltage is applied to the wire of letter "T", leading into the first scrambler. And on a test register attached to the last scrambler, the wire of letter "T" should have a voltage on it as well. If the setting is incorrect, a different letter will light up. Similarly, all incorrect inputs for this particular setup will always light up a different letter at the the end, never the same (thanks to the reflector). If output equals input, you're golden. And if several loops are used, all with the same input/output letter, each of their outputs must equal the input.

To reduce the number of false positives, you need as many connected loops within the crib as possible.

So far, that's an Enigma without a plugboard. To account for that, they introduced feedback loops into the circuit. In our small scale case, the output of the third scrambler would be coupled back into the input of the first scrambler. The number of loops determines the number of possible outcomes with each specific setting. All of these are fed back into the first scrambler of each loop.

The plugboard, however, changed the input into the system of rotors. Instead of a "T" in our example, it might be a "Z", if those two letters were connected on the board.

A random hypothesis is made and fed into the machine. If the scramblers are set incorrectly, a different letter comes out at the end of each loop and is in return fed back into the first scramblers. Result: (almost) everything lights up. If you start with a good graph, everything will light up.

-----
A key element for this was the "diagonal board", which represented a) all possible connections on the plugboard and b) the bidirectional nature of those connections (AB = BA). Maybe it can be explained without pictures, but I sure as hell can't, so "a grid of all possible connections between scramblers and letters + forced reciprocity" will have to suffice.
-----

If, however, the setting was correct, a wrong hypothesis for the input connection merely meant that everything except the right connections was lit up.

Let's say the fix point of the loops in our graph is the letter "T". We assume that it's connected to the letter "Z" on the plugboard. A voltage is applied to "Z" on the test register, and thereby inserted into the circuit at the first scrambler. Loop #1 applies voltage to the letter "A" on the test register, #2 lights up "B", #3 lights up "F". These three outputs are now fed back into the first scrambler, so now the scrambler has voltage on ZABF, which in return lights up ZABF+GEK on the test register.
This goes on until everything except "U" is lit up on the test register. That means three things: a) the settings are correct, b) the hypothesis is wrong, c) "T" is connected to "U".

Reasons:
a) if the settings were incorrect, the entire register would be alive
b) if the hypothesis was correct, only the letter "Z" would be alive on the register
c) due to the feedback loop, the only way for the output to be "U" is if the input was also "U", and the reciprocity within the system makes it impossible for any other input to generate the output "U". Since "T" was the fix point for our loops, "T" is connected to "U".

Similarly, if the initial hypothesis is correct, everything on the test register except "U" stays dead.

The diagonal board provides registers for every single letter and allows the user to pick one as a test register. During operation, all the other registers serve as visual representations of the deductions based on the initial hypothesis. So you actually get to see more than just the initial connection, all based on the same concept.

rychan said:

I do not understand at all why finding one contradictory plug setting, e.g. (t a) and (t g), means that every other plug setting you found during that trial was wrong. That cannot possibly be true. The space of possible plug connections (on the order of 26*25) is too small. You've probably got millions of trials that end in conflicting plug settings. You would end up invalidating all of them. I must be misunderstanding what he was trying to say.

Black Forest Cake... yum!



Send this Article to a Friend



Separate multiple emails with a comma (,); limit 5 recipients






Your email has been sent successfully!

Manage this Video in Your Playlists

Beggar's Canyon