Thursday, April 24, 2008

The Eat Sleep Shit Week (day 5)

The Eat-Sleep-Shit Week is a movement by Jolene Lai to relive the hey-days of blogging, to recover the ability or inclination to spew endless sentences about anything and everything.

"The rules are that you must type everything that happened to you in the past 24 hours and you can add any tid bits from the previous days."- Jolene Lai



***


The treatment system was being pressurised and tested sequentially today; it was quite eventful. The secondary feed line was pressurised to 2.5 Bar, and filter assembly #5 was found to be operational.

An engineer from the client dropped by to have a look. When he noticed some leaks (due to the high pressure, even minor crevices result in water squirting out in streams or mists), he asked if there were any problems. “All is fine,” our engineer told him, “In a project as big as this, little leaks are inevitable. We'll just tighten the leaky connections and reseal the welds and it'll be ok.”

Reassured, the client's engineer went away to worry about other things.


Filter assemblies 4, 3 and 2 were faulty and required patches. The inlet valve to #5 was closed, and the valve to #1 opened.

No reaction.

Check the flow meters. Is there water coming out via the waste line? What's the pressure like? Has the pipe been completely been bled of air?

I was standing next to the inlet valve of #1 when the pipe ruptured. All at once, there was a loud bang, a huge fragment from the PVC pipe hit me in the arm and I was drenched. I spewed some vulgarities as I made my way out of the cascade of water.

It hurts. Being blasted by that fragment is like being punched by someone who knows how to throw a punch. Judging from experience, I'd guess that spot will remain sore for some days.


So the pipe fractured. The parts will arrive tomorrow; there's no work going on. I milled about the site for a while, pondering a conversation from some dinners back.

They had talked about black holes and particle accelerators. Someone remarked that if a little black hole was created in an accelerator, the black hole would progressively suck in the earth and that would be the end of us.


[caution: black holes; scroll down]

My intuition told me otherwise- black holes do not suck; their gravitational attraction is exactly the same as that of any other normal mass. And black holes evaporate, a phenomenon called Hawking Radiation. The mass-loss rate of a black hole is inversely proportional to the square of the black hole's mass.

The mass is lost in the form of radiation, and as the black hole becomes smaller the mass loss rate increases rapidly, eventually resulting in a burst of gamma rays.

So, the question is, will the presence of a small black hole threaten the existence of mankind?

A simple solution in which the presence of a small black hole will not threaten our existence is one in which the black hole evaporates faster than it can assimilate mass from its surroundings.

The black hole's mass is no different from any other mass in that it behaves the same way in a gravitational field. Thus, a black hole will fall towards the centre of the earth due to the mutual attraction between the black hole's mass and the earth's mass.

The black hole is also absurdly dense compared to the everyday substances on earth, so it's path towards the centre of the earth will not be significantly obstructed. This is similar to a case in which a dense cannon ball falling towards the earth is not obstructed by the surrounding air.

The mass loss rate of a black hole can be directly inferred from it's mass. As the black hole moves through matter (air, earth, water, rock, condom storage facility), mass in its path (plus a margin on its sides) will be swept into the event horizon and thus contribute to the black hole's mass gain.

A set of differential equations can be formulated to generally describe the black hole's path as it falls towards the earth's centre and the black hole's mass change.

The rate of change in mass is the sum of Hawking Radiation (mass loss, function of M^-2) and mass gain in the form of swept mass as the black hole falls (velocity of black hole relative to the earth * cross-section area of event horizon * density of surrounding matter).

The cross-section of the event horizon is proportion to the square of black hole mass.

The velocity of the black hole relative to the earth is a described by the dif ferential equation describing the attraction of the black hole towards the centre of the earth, and the addition of stationary mass to the black hole.
[end caution]


I hope to properly express the equations and solve the differential equations numerically... one fine day.

With nothing to do on site except ponder the significance of black holes, I returned to the office. Once at my desk I removed my socks and shoes- they were soaked. My jeans were wet too, but it was impractical to remove them at the office.

8.30 pm – my arm still hurts. Blasted PVC pipe... it was a huge pipe too, 16 inches inner diameter and ~10 mm wall thickness.

I bumped into a wall earlier in the afternoon and realised how remarkably painful it is.

I'll be flying to Kuala Lumpur tomorrow, and moving house over the weekend. Therefore, Eat Sleep Shit posts will be on hold until further notice.

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