The universe's most abrasive substance.

H2O

H₂O? Nah!

My ex-wife's personality.

OMG! You married her, too? ;-)

She was a polygamist? I didn't know that!

-E

diamond for sure.

try if you r wearing one.

Sorry 'Guest'. It's still H20. Diamond is a matrix of carbon atoms. What does Hydrogen and Oxygen love the most? You figured it out.= Carbon.It will take a long time but it will happen.

After a while normal air will decompose a diamond into just carbon atoms. So Diamonds are really not forever.

Ask any geomorphogist what happens to mountains.

I would say the TIME is the most abrasive thing in the universe.It facilitates the wearing down of mountains into dirt,molehills into canyons, and world class boxers into blubbering idiots.

Is TIME a substance? I know it is a magazine, but possibly one without substance!

Water on its own doesn't do a lot - it's mostly when the water starts to pick up hard particles that the abrasion happens.

For example, you can use an ultra-high-pressure waterjet cutter to slice through 6" of steel (I've done it), but not much happens with pure water - you need to dope the water with an abrasive - typically garnet grit.

The same idea applies for air (as in sand- or grit-blasting, or naturally-occurring wind erosion).

Does it take time to cut?If so, see above.

Just get the meaning of abrasion.

it is a knid of mechanical action. so many corosive material are on earth but not abrasive.

It cant be h2O OR NaCl or anything that eat by corosion.

its has to be diamond,or topaz, or platinum or something else that is mechanically hard.

I'll give a clue. It sometimes also involves the use a foaming substance to faciltate the degradation of sharpest metal in use by a man.

Stubble!

Come on, 68torino, 'fess up. Your "" in the original post and the "foam" clue gave it away.

Now put us all out of our misery!

Would you be refering to foaming surf? As in salt water?

Steam

Here is a wild guess, light. Sunlight degrades many things, laser light can cut most things.

How about salt. NaCl

Man

thinking outside the square

In a word, the same thing that helps sustain life for us carbon-based life forms: Oxygen.

Ing. Robert Forbus

I'll vote for oxygen as the world's most evil disintegrator.

It's wedding cake! Wedding cake is the best known substance for stopping a woman from having sex also.

No abrasive substances work without motion. (I don't know where I was going with that, just a thought.)

As you're talking about abrasion and not chemical erosion, I'll have a stab at silicone, but I'm still thinking about it!

seawater

Torino

I think word abrasive is not right world for the question you are trying to ask.

chlorine

I want the posters definition of abrasion, and substance. Is time a substance? Is light a substance? The whole reality to one by defintion is illusion to another by definition. We need a common definition from the poster or it is all illusion. So my guess is reality. It abraids and dulls our innocence.

Although I proposed oxygen as being very destructive, I have to say I much prefer your answer!

Very small rocks.

Gravy?

Actually, I've seen both garnet (used as the abrasive in waterjet abrading, etching, etc.) and silicon carbide (for wet or dry grinding) used successfully with titanium alloys, and either will abrade all the other mentioned metals/alloys as well.

But "the universe" is a big place...though "abrasive" directs that the answer is crystalline, not liquid (since that would be corrosive); so would this require a naturally occuring, most-stable crystal structure that results in directly abrading other crystals like diamond, but is known to weaken (create dislocations as an impurity) in metal structures and alloys? Then I'm leaning more towards the silicon carbide.

I must confess I prefer the spectral refraction of Moissanite better than 'plain' diamonds, anyway.

I've often wondered, does a titanium blade have any titanium in its structure? I wouldn't think so as I have a SEAL knive with no magnetic signature made of titamium. The thing won't cut soft butter. The sharpest blade I've used was a santoku knife made by a japanese smith. This blade would cut thru a green peper by it's own weight (not too much). The edge was very brittle and tended to break up when used on a hard substance. I wrote an article in Fine Woodworking a few years (like 24!?) where we talked a lot about the steels, hardening and composition of various chisels as well as the comparative abilities to cut joints in hard materials. The Japanese tools got good marks for the hardness of the steel edge (64-69 Rockwell C) but hammering on the tool causes the edge to crumble and become dull requiring the chisel to be reground. It was interesting to me that the Footprint and, believe it or not, the Stanly came in one and two. The Stanly was made of a plain old dirty 1095 steel but it did the work nicely and cut all day long. By the way, I learned to shave with my dad's straightedge and to this day there is no better shave. The other advantage is that my wife would not think of using that edge!

This is a guess, because I did not know that razor blades were made of "titanium", but I believe that the so-called "titanium" blades are actually steel, stainless or tool steel, with a Titanium-Nitride (commonly called TiN) coating. TiN coatings are used in industry for drills, milling inserts, and other cutting tools. This would give the surface extreme hardness and wear resistance, but also excellent toughness due to the base metal, unlike the brittleness that might occur in a pure titanium metal blade. That, and the high cost of titanium, a relatively rare metal which is expensive to refine and process due to the very same properties that make it so valuable, strength and corrosion resistance, make it very unlikely that the metal is actually used, unless it is an alloying element in the steel.

Originally I liked the water idea, but the question did say that it is abrasive action, not chemical reaction, and it is the impurities in water that do the abraiding ... hmmm ... the EX is 80% water and the rest of her is impure ... but as to one substance?

How about Talc or reg ole baking soda?

If you mix an ex with a new, in too short a span of time, then the new will automatically be converted to an ex, and the abrasion factor can be calculated as the square of your suffering... and to answer your question about one substance, an ex is a singularity, and two exes combine to form a more abrasive singularity, and your event horizon will pucker right up, and will probably require immediate intervention from Jack Daniels, M.D.

:)

antimatter

'Dark' antimatter, which is known to release copius amounts of dark energy and dark neutrinos when brought into contact with leg stubble.

-E

OK, in orig. post, "it has weakened..." seems more like a chemical process like corrosion rather than physical abrasion. 68torino, do you really mean abrasion or corrosion or what? It is an interesting question.

'sands of time' :)

So Are the Days of Our Lives.

Any man who has tried to shave after a woman(usually his wife) has used his razor to shave her legs can attest to the most abrasive substance known to even dull titanium. Abrasive may not be precise but after the woman (ab)uses a titanium bladed razor and you try to SCRAPE your face with it. I'll bet you think "abrasive!!!!"

A womans hair. The Exwife was the closest guess!!

I know you mean this as a joke, somewhat tongue-in-cheek, but I wonder if your answer really rings true. By that I mean, has the razor's fine edge really been abraded, i.e. mechanically ripped, scarred, or broken, or has it just been bent and/or distorted, because the edge is so thin and does not have much resistance to bending moments, regardless of how "strong" the metal might be in absolute terms (ultimate strength in KSI). I believe that photomicrographs of a razor's edge might show this.

But if a man can use his razor a dozen times with little degrading or abrading of the edge, but a woman uses it just once with complete degradation of the cutting edge. Does that not speak to abrasion? It could be on a sub-micronic level or perhaps it has something to do with their anti-quark natures. If it were a chemical action as in acidic or caustic would we not then get our fingers burnt?

Glad my wife don't read this stuff

There are several possible explanations why a woman shaving her legs has more deleterious effect on a razor's sharpness than a man shaving his face.

One is simply the much larger surface area which is covered by shaving two legs than a single face. Another is that a woman is likely to press down harder, since 1. her aim is to avoid shaving again for as many days as possible and 2. her legs are less sensitive than facial skin and 3. she is less likely to cut herself over relatively long flat strokes versus many more short strokes, bumps, and curves on a man's face (despite the TV advertising to the contrary).

Finally, leg hair is simply more coarse than facial hair, perhaps an evolutionary throwback to when legs needed more protection (before pants, stockings, or tall boots) from the environment they travelled through. This coarseness make it stronger and harder to cut (more abrasive?) than facial hair. Women always complain about men's faces being prickly after a few days growth, but a woman's unshaven leg hairs (until they get long enough, au naturel) are like rosebush thorns!

JohnDG had most of the answer Kudos.

I'da prob'ly got the whole thing, if I'd ever been daft enough to let a woman near one of my razors ! ("Sorry" to any women out there - no offense intended).

hydrogn peroxide

dirt

Kinda like Inuit artists who use walrus whiskers to "drill" holes in ivory (walrus tusks). Hmmm... I still like europium's first reply though!

Abrasive to me, it's politicians and religious extremists.

Yes, but you can't deny that abrasives have their place. This is true even in the case of politicians and religious extremists. Politicians, for example, make excellent bad examples. (They're also an important source of protein.) And religious extremists? They're great for polishing atheists.

-e

So lets find the hook. The universe is an infinitely big place but since for our purpose we define the universe it is now much smaller, the known universe. If it has been known about for thousands of years then we must consider the intellectual capacity of who "we" were and exactly how many is thousands. I think we have to assume that the known universe was much smaller then and susequently the number of know substances in that universe much smaller. Now we must assess how abrasive, degrade(ed) and weakened are similar as they all relate to the process. Abrasion is a mechanical process which requires motion and at least 2 dissimilar substances for it to occur. Degredation and weakening can both result from the process.

So now I conclude that have no idea...................yet.

Aha! The universe, not the earth! So water is out. Also salt. Okay, let's try hydrogen.

But wait! Perhaps ice? As in glacial ice? As in comet ice? As in quarry ice? etc? As in yet-to-be-frozen ice as well?

Water

I know that this thread has been answered but just to be picky. I think that women have only been shaving their legs since the mid to late 20th century. They were not doing it in the 1970's.

And just to throw an answer into the mix---- Entropy.

"Remember, it's better to burn out than to fade away"

I recall hearing that some cultures plucked hairs with clam shells. Would that be considered abrasive?

That would be considered painful!

Not abrasive, per se. More like abusive.

I've heard of those cultures. For capital punishment don't they practice Death by Boogum?

-e

Interesting observation. At first I thought how strange that you would think that, and then realized that you are from a different part of the world than I am. In the US, effectively all women shaved their legs by the sixties. By then, having unshaven legs was an indicator of very strong affiliation with the women's liberation movement, and even then it was rare. My mother was very active in the women's lib movement, but nevertheless shaved.

In the US, men shaving their entire bodies is becoming increasingly common, particularly among young men. I find shaving my face alone to be a nuisance -- can't imagine wanting to take the time to shave everywhere.

The wiki article:

http://en.wikipedia.org/wiki/Leg_shaving

Ken, it may not always be the case of wanting to shave one's entire body. In the case of a number of engineers with whom I've worked it finally boiled down to their having to make a choice: shave, or face the compulsory sheep dip.

-e

It saddens me that you are so intolerant of vermin!

Oh… wait… no, I meant the bugs on the engineers, not the engineers themselves. Anyone who would willing put himself in the position of having to work with engineers is de facto tolerant.

You might wonder why I would say "willing" iso "willingly" above. It is part of my plan to be more concise. I'm hoping to drop letters in a random fashion.. hopefully in places where it make communicat as ambiguous as possible. (Wait. Did I mean to say unambiguous? Now that the instant is past, I don't know. BTW, just what is "time?")

clearly time is the most abrasive substance!

Of course, it doesn't hurt to have your HazMat gear in working order.

-e

I've been wondering what has been known since ancient times... and I think, other than water, it might be Fire.

In addition to that, the ancient gods apparently used advanced tools for stone cutting in several ancient constructions, including the great pyramid. One story involves the search by Solomon for an 'worm' known in 'ancient times' that could cut stone, because to build his new temple, no metal was permitted, and no hammer or chisel was allowed... and apparently he found his 'worm', and drew lines upon the stone, and it was subsequently cut. very provocative story. makes me wonder.

I also find it interesting the story about the stone city in polynesia, whose stone came from another island 100 miles away, and the ancient myths say that "the stones came floating across the water to the sound of music"...

chris

a link to the worm story.

http://www.jhom.com/topics/stones/shamir.html

a quote from the story.

"Solomon was informed by a wise counselor of a most marvelous creature, about the size of a single grain of barley, which was so strong that it could cut through any substance on earth, even the hardest of diamonds; in fact, it could cut stone better than the sharpest tool of iron. "

fire is a chemical reaction, not a substance

You wrote: "the stones came floating across the water to the sound of music"

Are you here referring to one of the deleted scenes from that film starring Julie Andrews and Christopher Plummer? I like the uncut version better - especially the part where they're all sitting around toking on that gawdawful, jimongous hookah.

-e

actually i was discussing this topic with an engineer before ( as i am still a student) and he told me that the most corrosive substance in the world in inside your mouth

BUT THIS IS CORROSIVE NOT ABRASIVE

The universal solvent... Sorry, container not available.

65 million years ago, a rogue interstellar body came hurtling through the void, and collided with Tiamat, smashing the planet virtually in half, creating the 'hammered bracelet' (asteroid belt), and blowing tremendous volumes of water out to mars and neptune, and beyond. The gaping hole eventually healed over, and is now the pacific ocean, but the event killed all life down to the plankton level, and brought a sudden catastrophic end to all large life on this planet (now called Earth or Gaia)

This story was told to the people in Sumeria 6000 years ago, and is recorded on clay tablets found in the ruins of Ninevah, palace of Ashubanipal (5000 yrs old) in modern day Iraq. It's original source was from the 'gods' (Zecharia Sitchin - The Twelfth Planet)

This event was globally abrasive.

:)

Abrasive? Perhaps. Ablative? Definitely.

-e

Never trust an engineer.

ending.

"It bugs me when a sentence like this doesn't have an" - Blink

"ending" - Europium

Oh, c'mon, way to obvious! Here's my top ten, way better "endings":

1. "appreciative audience"

2. "ounce of imagination"

3. "immediate attention-grabber"

4. "artificial construct"

5. "existential basis for comparison"

6. "evil twin"

7. "irritating whininess"

8. "impartial thesis"

9. "empty-headed ending writer"

And the #10 better "ending":

10. "actual purpose"

Having drawn attention to the sad fact that I occasionally leave a out of my sentences, you should be ashamed! Well let me make something crystal clear. The whole point of this sentence is to make clear the whole point of this sentence.

From this you can see how easy it is to waste time. Therefore, I can only say to you, remember Blink's Law. Blink's law states that it always takes longer than you think it will, even if you take into account Blink's law. Blink stole his law from Douglas Hofstadter.

Well, all I can say is, the first thing to go when you get my age is memory.

The second thing to go when you get my age is memory.

This reminds me of a lecture I think I once missed.

If I may quote (from memory):

An immediate attention-grabber for an appreciative audience without an ounce of imagination is the existential basis for comparison between the evil twins: "artificial construct" and "impartial thesis". This can, however, lead to irritating whininess from an empty-headed ending writer with no actual purpose. There is no

But maybe that was when I fried up those funny little mushrooms, and found the Philosophy of Fine Art class.

Wet sandy pumice grit with crumbs and

Hey, that last bit reminds me of my honeymoon ...

As was mentioned in an earlier post, some refining of definitions may be in order.

It would appear, judging by the responses, that the correct answer is leaning towards a woman's leg hair and its less than desirable effects.

That being said, I defy anyone to dull a razor by simply setting it down on a woman's leg and not doing anything more with it. It must be that the term "abrasive" is used loosely as abrading requires at least three components; a hard substance, energy in the form of mechanical force and something to abrade (the razor).

In metallurgy, the terms "tough, hard, strong and ductile" are used to describe specific physical properties of an alloy. Toughness is a measure of a material's ability to absorb or withstand impact forces, ductility refers to an alloys ability to be deformed plasticly in tension (malleable in compression). a strong material is one that resists deformation both elastic and plastic and a hard material can better withstand wear or abrassion and this can imply brittleness (unless case hardening or nitriding etc. has been done).

Perhaps the questioner meant "what is the hardest substance"?

Definitely not leg hair!

Good old water my friend. In due time it will cut through evryting.

It's the IRS.

Pumice

OK, now just stop IT! The originator of this challenge gave his "definitive" answer in #36, obviously meant to be tongue-in-cheek humor, so quit posting to this thread and find something better to do!!!!!!!!!

As I don't think that titanium or nitrides were well known in ancient times, I'm still curious as to his 'real' answer... :) at least I was hoping there was a real answer...

chris

I'm pretty sure there wasn't a 'real' answer - and have been since his post #9 - 68torino correct me if I'm wrong.

Yes it was quite tounge in cheek. I have found it to be most amusing at some posters still arguing the point after I gave the 'answer'. Those who don't think a woman's leg hairs are abrasive haven't tried to shave after they used your razor once. I can shave several times before the blade9s) get dull. My wife uses it once and I'd swear she tried to skin a cinder block. But let's move on to other more productive problem solving.

And thanks to all

There is one fact from my experience that I didn't use, which may have yielded your ('correct') solution - the abrasive effect (albeit subjective) of a womans leg with 3-day-old stubble on any part of my anatomy. 'Nuff sed .

Information is the most abrasive substance-it changes everything, instantly, with no action required.

Proof: I felt perfectly normal prior to reading this thread, now I have this foolish feeling, yet I never moved.

By Jove, I think you've got it!

For months we've puzzled over what mysterious mechanism might be causing the rapid deterioration of our network cables. They're a mess! Just mere filaments!

Even this morning I noticed that the brand-spanking-new CAT5 cable I plugged into my system last night was in tatters this morning; not in just one spot, but over its entire length. Come to think of it, this happens every time I do a big download.

Abrasives are not necessarily a Bad Thing, however. Just think of all the applications which use abrasives to their advantage. Like grinders, polishers; stuff like that...

Brrrrring!

"May I help you?"

"As a matter of fact, you can. I'm looking for some 4GB wet/dry sandpaper, 32-bit grit. Got any on hand?"

"Oh yes we do indeed! Just got a new shipment in last night. How much do you need?"

"I think one terabyte will do just fine, thanks. Oh, by the way..."

"Yes?"

"How do you safely dispose of this stuff when you're done with it?"

"Oh, that's easy. Just take it to your neighborhood recycling center and they'll archive what's left."

"What about the stuff that wears off and messes up my clean workbench?"

"Just sweep it into one of these here bit-buckets and you're all set. Anything else?"

"Yes, give me two of your best bit-buckets and one of those digital brooms. Yeah, that one over there; the one with the blue RJ-45 jack and holographic display."

"Will this be cash, debit, or credit?"

"Debit."

"...."

"I'm sorry, Sir, your card seems to be all out of abrasives. Would you like to pay in cash or put this on your credit card?"

"No sir; I don't carry cash and I don't use credit cards. Do you take sandpaper?"

-e

"By Jove, I think you've got it!"....

"I'm sorry, Sir, your card seems to be all out of abrasives...."

All I can say is, "Illegitimati non carborundum!"

Oh come now, STL Engineer! Let's face it: clearly even you've read this far, haven't you?

-E

Just goes to show that the way to hold our attention is to provide an avenue for the imagination to go full throttle. The longest threads are usually the least informative, but the most fun.

Doesn't anyone wonder if 68Torino actually has a 1968 Ford Torino? Or if he went to school in Torino, Italy? There must be some way to breathe new life into this thread!

Ok, New life? How about a question from left field.

Prove that there are no bones in icecream?

This comes from the Question.

Q. Why do fish swim? A. Because there are no bones in icecream.

That's a pretty fishy question, no bones about it.

-e