Saturday, December 17, 2016

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Monday, November 21, 2016

tip ์•ˆ๋“œ๋กœ์ด๋“œ 6 ๋งˆ์‹œ๋ฉœ๋กœ ํ™ˆํ™”๋ฉด ํด๋” ๊ด€๋ฆฌ

1. ์Šค๋งˆํŠธํฐ ํ™ˆํ™”๋ฉด(๋ฐ”ํƒ•ํ™”๋ฉด)์— ๋งŽ์€ ์•ฑ๊ณผ ์œ„์ ฏ์ด ๋งŽ์„ ๋•Œ ํด๋”๋ฅผ ๋งŒ๋“ค์–ด ๋น„์Šทํ•œ ์•ฑ์„ ๋„ฃ์–ด๋‘๋ฉด ์ข‹๋‹ค.

2. ์•ฑ์€ ํด๋”์— ๊ด€๋ฆฌํ•  ์ˆ˜ ์žˆ์ง€๋งŒ, ์œ„์ ฏ์€ ํด๋”์— ๋„ฃ์„์ˆ˜ ์—†๋‹ค.

3. ํด๋”๋ฅผ ๋งŒ๋“œ๋Š” ๋ฐฉ๋ฒ•: ํ™ˆํ™”๋ฉด์— ์žˆ๋Š” ์•ฑ A์™€ B๋ฅผ ๊ฐ™์€ ํด๋”์— ๋„ฃ๋Š”๋‹ค๊ณ  ๊ฐ€์ •ํ•˜๋ฉด, A๋ฅผ ๋ˆ„๋ฅธ ์ƒํƒœ์—์„œ ๋Œ์–ด์„œ B ์œ„์— ์˜ฌ๋ ค๋†“์œผ๋ฉด ์ž๋™์œผ๋กœ ํด๋”๊ฐ€ ์ƒ์„ฑ๋˜๊ณ , ํด๋” ์ด๋ฆ„ ๋ฐ ์ƒ‰์„ ์ง€์ •ํ•  ์ˆ˜ ์žˆ๋‹ค. (์œ„์ ฏ์€ ์ด๋ ‡๊ฒŒ ํ•ด๋„ ํด๋”๊ฐ€ ์ƒ์„ฑ๋˜์ง€ ์•Š๋Š”๋‹ค)

4. ์œ„์ ฏ์„ ํด๋”์— ๊ด€๋ฆฌํ•˜๋ ค๋ฉด ๋‹ค๋ฅธ ํด๋”๊ด€๋ฆฌ ์•ฑ์„ ์‚ฌ์šฉํ•ด์•ผ ํ•˜๋Š”๋“ฏ (๋ฏธํ™•์ธ)


Monday, February 29, 2016

[์ฑ…] ๋ฉ€ํ‹ฐ์œ ๋‹ˆ๋ฒ„์Šค The hidden reality by Brian Greene

 ๋ฌผ๋ฆฌํ•™๊ณผ ์ˆ˜ํ•™์œผ๋กœ๋ถ€ํ„ฐ ์œ ๋„ ๋˜๋Š” ์œ ์ถ”ํ•  ์ˆ˜ ์žˆ๋Š” ํ‰ํ–‰์šฐ์ฃผ - ์šฐ๋ฆฌ๊ฐ€ ์‚ด๊ณ  ์žˆ๋Š” ์šฐ์ฃผ์™€ ๊ณต๊ฐ„/์‹œ๊ฐ„์ ์œผ๋กœ ๋‚˜๋ž€ํžˆ ์กด์žฌํ•˜๋Š” ์ˆ˜ ๋งŽ์€ ๋˜ ๋‹ค๋ฅธ ์šฐ์ฃผ - ์— ๋Œ€ํ•œ ์ฑ…. ์—ฌ๋Ÿฌ ์ €์ž‘์˜ ๊ฒฝํ—˜์—์„œ ๋‚˜์˜จ ๊ฒƒ์ธ์ง€, ์–ด๋ ค์šด ๋ถ€๋ถ„์€ ์ ์ ˆํžˆ ์ฃผ์„์œผ๋กœ ๋Œ๋ฆฌ๊ฑฐ๋‚˜, ์ด ์žฅ์˜ ๋งˆ์ง€๋ง‰์€ ๋„˜์–ด๊ฐ€๋„ ์ข‹๋‹ค๋Š” ์‹์˜ ์นœ์ ˆํ•จ์œผ๋กœ ๋ง‰ํž˜ ์—†์ด ์ฝ์„ ์ˆ˜ ์žˆ๋‹ค. ์‚ฌ์‹ค ๋ ˆ๋„ˆ๋“œ ์„œ์Šคํ‚จ๋“œ(๋ธ”๋ž™ํ™€ ์ „์Ÿ)์— ๋น„ํ•˜๋ฉด ๊ทน์ ์ธ ๋ฉด(๋˜๋Š” ๊ณผ์žฅ?)๊ณผ ์žฌ๋ฏธ๋Š” ๋œ ํ•˜์ง€๋งŒ, ๋Œ€์‹  ์„œ์Šคํ‚จ๋“œ๋ณด๋‹ค ์ •๋ฆฌ๋Š” ๋” ์ž˜ํ•ด ์ดํ•ด๋Š” ์‰ฝ๋‹ค.
 ์šฐ์ฃผ ํƒ„์ƒ์— ๊ด€ํ•œ ์•ค๋Ÿฐ ๊ตฌ์Šค์˜ ์ธํ”Œ๋ ˆ์ด์…˜ ์ด๋ก , ๋ธ”๋ž™ํ™€ ์—”ํŠธ๋กœํ”ผ ๋…ผ์Ÿ์œผ๋กœ๋ถ€ํ„ฐ ํŒŒ์ƒ๋œ ํ™€๋กœ๊ทธ๋žจ ์šฐ์ฃผ, ๋ˆ ์ด๋ก , M ์ด๋ก  ๋“ฑ์„ ์—ฐ๊ตฌํ•˜๋Š” ๊ณผ์ •์—์„œ ์ˆ˜ํ•™์  ์ •ํ•ฉ์„ฑ์œผ๋กœ ๋“ฑ์žฅํ•œ ๊ฐ๊ฐ์˜ ๋ฉ€ํ‹ฐ๋ฒ„์Šค (์„œ์Šคํ‚จ๋“œ๋Š” ์ด๋ฅผ ๋ฉ”๊ฐ€๋ฒ„์Šค๋ผ๊ณ  ๋ถ€๋ฅด์ง€๋งŒ ๋ฉ€ํ‹ฐ๋ฒ„์Šค๊ฐ€ ๋” ๋งŽ์ด ์“ฐ์ž„)๊นŒ์ง€๋Š” ๊ทธ๋Ÿฐ๊ฐ€๋ณด๋‹ค ํ•˜๊ฒ ๋Š”๋ฐ... ์˜ํ™” ๋งคํŠธ๋ฆญ์Šค ๋ฅ˜์˜ ์‹œ๋ฎฌ๋ ˆ์ด์…˜๋œ ์šฐ์ฃผ๊นŒ์ง€ ์ œ๋ฒ• ์ง„์ง€ํ•˜๊ฒŒ ๋…ผํ•  ๋•Œ๋Š” ํ˜€๋ฅผ ๋‚ด๋‘๋ฅผ ์ˆ˜๋ฐ–์—.
 ๊ฐœ์ธ์ ์œผ๋กœ ์‹œ๋ฎฌ๋ ˆ์ด์…˜ ์šฐ์ฃผ๋Š” ์ข€ ๋ฐ›์•„๋“ค์ด๊ธฐ ํž˜๋“ค์ง€๋งŒ, ์˜ˆ๋ฅผ ๋“ค์–ด ์ €์ž๋Š” ์‹œ๋ฎฌ๋ ˆ์ด์…˜ ์šฐ์ฃผ์˜ ๊ฒ€์ฆ ๋ฐฉ๋ฒ•์œผ๋กœ ์–ธ์  ๊ฐ€ ์šฐ๋ฆฌ๊ฐ€ ์ธ๊ณต์ง€๋Šฅ์„ ๊ฐœ๋ฐœํ•  ์ˆ˜ ์žˆ๋‹ค๋ฉด ์šฐ๋ฆฌ ์šฐ์ฃผ์™€ ๊ฐ™์€ ์‹ฌ์‹œํ‹ฐ, ์„ธ์ปจ๋ผ์ดํ”„ ๋ฅ˜์˜ ์‹œ๋ฎฌ๋ ˆ์ด์…˜์„ ์ˆ˜ํ–‰ํ•  ์ˆ˜ ์žˆ๊ณ , ์‹œ๋ฎฌ๋ ˆ์ด์…˜ ๋‚ด ์šฐ์ฃผ์˜ ์ธ๊ฐ„์€ ์ž์•„๋ฅผ ๊ฐ€์งˆํ…Œ๊ณ , ์ˆ˜ ๋งŽ์€ ์ด๋Ÿฐ ๋ฅ˜์˜ ์‹œ๋ฎฌ๋ ˆ์ด์…˜์—์„œ ์‹œ๋ฎฌ๋ ˆ์ด์…˜์„ ์ฐฝ์กฐํ•œ ์ธ๊ฐ„๊ณผ ๊ทธ ์‹œ๋ฎฌ๋ ˆ์ด์…˜ ์† ์ธ๊ฐ„์˜ ๋งŒ๋‚จ์€ ํ™•๋ฅ ์ ์œผ๋กœ ์ž์—ฐ์Šค๋Ÿฌ์šด ๊ฒƒ์ด๋ผ๋Š”๋ฐ... ๊ทธ๋ ‡๋‹ค๋ฉด ์šฐ๋ฆฌ๋Š” ์™œ ์•„์ง๊นŒ์ง€ ์šฐ๋ฆฌ๋ฅผ ์ฐฝ์กฐํ•œ ์‹œ๋ฎฌ๋ ˆ์ดํ„ฐ๋ฅผ ๋งŒ๋‚˜์ง€ ๋ชปํ•œ๊ฑธ๊นŒ?
 ์•”ํŠผ ์ €์ž๊ฐ€ ํ˜„์žฌ์˜ ๊ณผํ•™ ์ˆ˜์ค€์œผ๋กœ ์‹คํ—˜/๊ด€์ฐฐ ๋ถˆ๊ฐ€๋Šฅํ•œ ์šฐ์ฃผ๋ฅผ ์•„ํ™‰๊ฐœ ์”ฉ์ด๋‚˜ ๋…ผํ•˜๋Š” ์ง„์˜๋Š” ์ˆ˜ํ•™์— ๋Œ€ํ•œ ์ €์ž์˜ ๋ฏฟ์Œ๊ณผ ๊ฒฝํƒ„์„ ๋…์ž๋“ค์—๊ฒŒ๋„ ์ „๋‹ฌํ•˜๊ณ  ์‹ถ์—ˆ๋˜ ํ„ฐ์ผ๋“ฏ. ๊ทธ๋Ÿฐ ๋ฉด์—์„œ ์›์ €์˜ ์ œ๋ชฉ ์ˆจ๊ฒจ์ง„ ์ง„์‹ค(hidden reality)์€ ๊ฒฐ๊ตญ ์ˆ˜ํ•™ ์ผ์ง„๋Œ€, ์ด๋ฅผ ๋ฉ€ํ‹ฐ์œ ๋‹ˆ๋ฒ„์Šค๋กœ ๋ฒˆ์—ญํ•œ ํŒจ๊ธฐ๋Š” ์ €์ž์˜ ์˜๋„๋ณด๋‹ค ์ฑ…์˜ ํŒ๋งค๋Ÿ‰์— ๋” ์‹ ๊ฒฝ์„ ์“ด ๊ฒƒ์ผ์ง€๋„. ์‚ฌ์‹ค ์ด๋ ‡๊ฒŒ ๋‘๊บผ์šด ์ฑ…์„ ์ œ๋ชฉ์ด ์–ด๋– ํ•œ๋“ค ํŒ๋งค๋Ÿ‰์— ๋ฌด์Šจ ๋ณ€ํ™”๊ฐ€ ์žˆ์„๊นŒ? ๊ทธ๋Ÿฌํ•œ ์ œ์•ฝ์—๋„ ์ด๋ ‡๊ฒŒ ์‰ฝ๊ณ  ์žฌ๋ฏธ์žˆ๋Š” ์ฑ…์„ ๊ณ ๋ฅธ ํ–‰์šด์— ๊ฐ์‚ฌํ•  ๋ฟ. ๊ทธ์˜ ๋ฒ ์ŠคํŠธ์…€๋Ÿฌ ์•จ๋Ÿฌ๊ฑดํŠธ ์œ ๋‹ˆ๋ฒ„์Šค (elegant universe)๋„ ๊ฒฐ๊ตญ ์ฝ๊ฒŒ ๋ ๋“ฏํ•˜๋‹ค.

Sunday, February 21, 2016

[์ฑ…] ์•ˆํƒ€๊นŒ์šด ๊ณ ๋ฆฌ์ค‘๋ ฅ์ด๋ก  by ๋ฆฌ์Šค๋ชฐ๋ฆฐ

์–‘์ž์—ญํ•™๊ณผ ์•„์ธ์Šˆํƒ€์ธ์˜ ์ค‘๋ ฅ์ด๋ก (์ผ๋ฐ˜์ƒ๋Œ€์„ฑ์ด๋ก )์„ ํ†ตํ•ฉํ•˜๋Š”๊ฒŒ ํ˜„๋Œ€ ๋ฌผ๋ฆฌํ•™์˜ ์ง€์ƒ ๊ณผ์ œ๋ผ๋Š” ๊ฒƒ์„ ์•Œ์•˜๋‹ค. ๊ทธ ์ค‘์‹ฌ์— ๋ˆ ์ด๋ก ์ด ์žˆ๊ณ , ์†Œ์ˆ˜์˜ ๊ณ ๋ฆฌ์ค‘๋ ฅ์ด๋ก ์ด ์žˆ๋‹ค๋Š”๋ฐ. ๋ˆ์ด๋ก ๊ฐ€์ธ ๋ ˆ๋„ˆ๋“œ ์„œ์Šคํ‚จ๋“œ ์ฑ…์„ ๋„ˆ๋ฌด ์žฌ๋ฏธ์žˆ๊ฒŒ ๋ณธ ํ„ฐ๋ผ, ๊ทธ ๋ฐ˜๋Œ€ํŽธ์˜ ๋Œ€๊ฐ€๋ผ๋Š” ๋ฆฌ์Šค๋ชฐ๋ฆฐ์˜ ์ƒ๊ฐ์ด ๊ถ๊ธˆํ–ˆ๋‹ค. ์ผ๋‹จ ๋‚ด๊ฐ€ ๋ณธ ์„œ์Šคํ‚จ๋“œ์˜ ์ฑ…๋“ค์— ๋น„ํ•ด ๋ฆฌ์Šค๋ชฐ๋ฆฐ์˜ ์ฑ…์€ ๋งค์šฐ ์–‡์•„ ์ข‹์•˜๋‹ค. ํ•˜์ง€๋งŒ ๋„ˆ๋ฌด ์ง€๋ฃจํ•˜๋‹ค๋Š”๊ฑฐใ… . ๊ฒŒ๋‹ค๊ฐ€ ๊ณ ๋ฆฌ์ค‘๋ ฅ์ด๋ก ๋„ ์ž˜ ๋ชจ๋ฅด๊ฒ ๋Š”๋ฐ ๊ทธ์˜ ์ฑ…์€ ๊ณ ๋ฆฌ์ค‘๋ ฅ์ด๋ก ๊ณผ ๋ˆ ์ด๋ก ์˜ ํ†ตํ•ฉ์— ๋Œ€ํ•ด ์ด์•ผ๊ธฐํ•˜๊ณ  ์žˆ๋‹ค. ์ผ๋ฉด ์‚ฌ๋ ค ๊นŠ์€ ํ–‰๋™์ผ์ˆ˜๋„ ์žˆ์ง€๋งŒ, ๊ฐ์ž๋Š” ์ž์‹ ์˜ ์‹ ๋…์ด ์˜ณ๋‹ค๋ฉด ๋๊นŒ์ง€ ์ž์‹ ์˜ ์ด๋ก ์— ์˜ํ˜น์ด ์—†๋„๋ก ๋…ธ๋ ฅํ•˜๋Š”๊ฒŒ ๋จผ์ €์ด์ง€ ์•Š์„๊นŒ? ๋ญ”๋ง์ด๋ƒ๋ฉด ์–‘ ์ด๋ก ์˜ ํ†ตํ•ฉ์„ ๋งํ•˜๊ธฐ ์ „์—, ์ž์‹ ์˜ ๊ณ ๋ฆฌ์ค‘๋ ฅ์ด๋ก ์„ ์„คํŒŒํ•˜๋Š”๋ฐ ์ตœ์„ ์„ ๋‹คํ–ˆ๋ƒ๋Š”๊ฑฐ๋‹ค. ํ•œ๊ตญ ์ง€๋ฐฉ ์‹œ๋ฆฝ ๋„์„œ๊ด€์—์„œ ๋‚˜๋Š” ๋ฆฌ์Šค๋ชฐ๋ฆฐ์ด ๊ฐ•๋ ฅํ•˜๊ฒŒ ์ฃผ์žฅํ•˜๋Š” ๊ณ ๋ฆฌ์ค‘๋ ฅ์ด๋ก ์˜ ์ฑ…์„ ๋ณด์ง€ ๋ชปํ–ˆ๋‹ค๋Š”๋ฐ ๋ฌธ์ œ๊ฐ€ ์žˆ๋‹ค. ๊ฒŒ๋‹ค๊ฐ€ ๋ฌธ์ฒด๋„ ๊ณ ๋ฆฌํƒ€๋ถ„ํ•˜๋‹ˆ ์„œ์Šคํ‚จ๋“œ์— ๋น„ํ•ด ์žฌ๋ฏธ์—†๋Š” ์‚ฌ๋žŒ์ผ๊ฒƒ์œผ๋กœ ์ถ”์ •๋œ๋‹ค. ๊ทธ๋ž˜๋„ ์†Œ์ˆ˜ ์˜๊ฒฌ์— ๋งค์šฐ ๊ด€์‹ฌ์ด ๋งŽ์€ ๋‚˜๋กœ์„œ, ๊ฒŒ๋‹ค๊ฐ€ ์ง„์‹ค์€ ๋ˆ/M์ด๋ก ๋ณด๋‹ค ๊ณ ๋ฆฌ์ค‘๋ ฅ์ด๋ก ์ผ์ง€๋„ ๋ˆ„๊ตฌ๋„ ๋ชจ๋ฅด๋Š”๋ฒ•, ์ œ๋ฐœ ๊ณ ๋ฆฌ์ค‘๋ ฅ์ด๋ก ์˜ ์žฌ๋ฐŒ๋Š” ์ฑ…์ข€ ์จ์ฃผ์„ธ์š”~ ๊ทผ๋ฐ ์ด๋ถ„ ์•„์ง ์‚ด์•„๊ฒŒ์‹œ๊ฒ ์ง€?

[์ฑ…] ์ด๋ฆ„๊ฐ’ํ•˜๋Š” ๊ดด์งœ๊ฒฝ์ œํ•™ Freakonomics

๋ฒ”์ฃ„, ๋งˆ์•ฝ, ์„น์Šค ๋“ฑ์„ ๋ฏธ์‹œ๊ฒฝ์ œํ•™์˜ ๋Œ€์‚ฌ์— ํฌํ•จํ•œ ์‹œ๋„๋Š” ํฅ๋ฏธ๋กญ๋‹ค. ์ €์ž ์ค‘ ํ•œ๋ช…์ธ ๊ฒฝ์ œํ•™๊ณผ ๊ต์ˆ˜๋Š” ๋ณธ์ธ์ด ๋ฐํ˜”๋“ฏ ์‹œ์นด๊ณ ํ•™ํŒŒ์™€ ์–ด์šธ๋ฆฌ์ง€ ์•Š์Œ์—๋„ ์Šค์นด์›ƒ ๋๋‹ค๋Š”๋ฐ. ๊ฒฝ์ œํ•™ ์ž˜ ๋ชจ๋ฅด๋Š” ๋‚ด๊ฐ€ ๋ณด๊ธฐ์—” ์‹œ์นด๊ณ ํ•™ํŒŒ๊ฐ€ ์ด์ œ ๋ณ„๋กœ ํ• ๊ฒŒ ์—†์–ด ์˜์—ญ์„ ๋„“ํžˆ๋Š”๊ฒŒ ์•„๋‹๊นŒ์‹ถ๋‹ค. ์žฌ๋Šฅ์€ ์žˆ์ง€๋งŒ ๋ช‡๋ช‡ ํ†ต๊ฒŒ์— ๋Œ€ํ•œ ๋ถ„์„์€ ๋‚ด ์ƒ์‹๊ณผ ๋งž์ง€ ์•Š๋Š”๊ฒŒ ๋ˆˆ์— ๋ˆ๋‹ค. ์ง€๊ธˆ ์ƒ๊ฐ๋‚˜๋Š” ๊ฒƒ์€ ์Œ์ฃผ์šด์ „๋ณด๋‹ค ์Œ์ฃผ๋ณดํ–‰์˜ ์‚ฌ๋ง์œจ์ด ๋” ๋†’๋‹ค๋Š”๊ฑด๋ฐ. ๋‚˜๋ฆ„์˜ ํ†ต๊ณ„๋ฅผ ๋‚ด์„ธ์› ์ง€๋งŒ ์›Œ๋‚™ ์ƒ์‹์— ๋ฐ˜ํ•˜๋‹ˆ ์–ด์˜๊ฐ€ ์—†์„์ •๋„. ์‚ฌ๊ณ ์œจ์— ์žˆ์–ด ์šด์ „๊ณผ ๋ณดํ–‰์„ ๊ฑฐ๋ฆฌ ๋‹จ์œ„๋กœ ๋น„๊ตํ–ˆ๋Š”๋ฐ, ๋‘˜์˜ ์†๋„ ์ฐจ์ด๊ฐ€ ์›Œ๋‚™ ํฌ๊ณ  ์‹ค์ œ ์ƒํ™œ์„ ๋ด๋„ ๊ฑฐ๋ฆฌ๋ณด๋‹ค๋Š” ์‹œ๊ฐ„์„ ๋น„๊ตํ–ˆ์–ด์•ผ ๋งž์ง€ ์‹ถ๋‹ค. ์˜ˆ๋ฅผ ๋“ค์–ด ์šด์ „ 10km์™€ ๋ณดํ–‰ 10km๋ฅผ ๋น„๊ตํ•œ๋‹ค๋ฉด, ๋ˆ„๊ฐ€ 10km๋‚˜ ๊ฑธ์„์ˆ˜ ์žˆ๋‚˜? ์ฐจ๋ผ๋ฆฌ ์šด์ „ 10๋ถ„๊ณผ ๋ณดํ–‰ 10๋ถ„์„ ๋น„๊ตํ•˜๋Š”๊ฒŒ ์ƒ์‹์ ์ด์ง€. ๊ทธ๋ž˜๋„ ๋ญ ์›Œ๋‚™ ์žฌ๋Šฅ์žˆ๊ณ  ๋‹ค์–‘ํ•œ ๋Œ€์ƒ ์„ญ๋ ต์€ ์ธ์ •ํ•ด๋„, ํŽธ๊ฒฌ์ธ์ง€ ๋ชฐ๋ผ๋„ ์•„๋‹ˆ๋ฉด ๋ง๊ณ  ์‹์˜ ๋…ผ๋ฆฌ?๊ฐ€ ๊ฑฐ์Šฌ๋ฆฐ๋‹ค.

[์ฑ…] ๋ธ”๋ž™ํ™€์—์„œ ํ”ผ์–ด๋‚œ ์–‘์ž์ค‘๋ ฅ์ด๋ก 

๋‚˜์˜ ๋ชจ๊ตใ…‹์ธ ์Šคํ…ํฌ๋“œ ๋ฌผ๋ฆฌํ•™๊ณผ ๊ต์ˆ˜ ๋ ˆ๋„ˆ๋“œ ์„œ์Šคํ‚จ๋“œ์˜, ์ œ๋ชฉ์€ ๊ธฐ์–ต๋‚˜์ง€ ์•Š์ง€๋งŒ ์šฐ์ฃผ๋ก  ๊ด€๋ จ ์ฑ…๊ณผ, ํ˜ธํ‚น๊ณผ ๋ฒŒ์ธ ๋ธ”๋ž™ํ™€ ์ „์Ÿ ์ฑ…์„ ์ตœ๊ทผ์—์•ผ ์ฝ์—ˆ๋‹ค. ์ด ์–‘๋ฐ˜ ์ถœ์‹ ์ด ๊ฐ€๋‚œํ•œ ์ง‘์•ˆ์ด๋ผ ๊ทธ๋Ÿฐ์ง€ ๋ชฐ๋ผ๋„ ์ง์„ค์ ์ธ ์œ ๋จธ์™€ ๋…ผ์ง€์˜ ์ „๊ฐœ๊ฐ€, ์ ์–ด๋„ ์ƒ๋Œ€์ ์œผ๋กœ ๊ณ ๋ฆฌํƒ€๋ถ„ํ•œ ๊ณ ๋ฆฌ์ค‘๋ ฅ์ด๋ก ์˜ ๋Œ€๊ฐ€ ๋ฆฌ ์Šค๋ชฐ๋ฆฐ๋ณด๋‹ค ํ›จ~~~์”ฌ ์žฌ๋ฏธ์žˆ๋‹ค. ์šฐ์ฃผ๋ก  ๊ด€๋ จ์ฑ…์€ ๋ˆ์ด๋ก  ์†Œ๊ฐœ ์ •๋„๋กœ ๊ฐœ๋ก ์ ์ด๋ผ ํ•œ๋ฒˆ๋งŒ ์ฝ์–ด๋„ ๋ฌด๋‚œํ•œ๋ฐ, ๋ธ”๋ž™ํ™€ ์ „์Ÿ์€ ๋‹ค ์ฝ๊ณ  ๋‚˜๊ณ  ์ด๊ฒŒ ์ „์Ÿ์ด ๋๋‚œ๊ฑด์ง€ ๋ˆ„๊ฐ€ ์ด๊ธด๊ฑด์ง€ ์ž˜ ๋ชจ๋ฅด๊ฒ ๋”๋ผใ…‹. ๋‘ ๋ฒˆ ์ฝ๊ณ  ๋‚˜๋‹ˆ ์–‘์ž์ „๊ธฐ์—ญํ•™, ์–‘์ž์ƒ‰์—ญํ•™, ๋ˆ์ด๋ฅธ, M์ด๋ก ์„ ์ค‘์‹ฌ์œผ๋กœ ์•„์ธ์Šˆํƒ€์ธ์˜ ์ค‘๋ ฅ์ด๋ก ์„ ๋ธ”๋ž™ํ™€์— ๋Œ€ํ•œ ์—”ํŠธ๋กœํ”ผ ๋…ผ์Ÿ์„ ํ†ตํ•ด ํ†ตํ•ฉํ•˜๋ ค๋Š” ์‹œ๋„๋ฅผ ์ƒ์ƒํžˆ ๋А๋‚„์ˆ˜ ์žˆ์–ด ์ข‹์•˜๋‹ค. ๋ธ”๋ž™ํ™€ ์ „์Ÿ์€ ๊ผญ ๋‘๋ฒˆ ์ฝ๊ธฐ๋ฅผ ์ถ”์ฒœ. ์ด๋ ‡๊ฒŒ ์ข‹์€ ์ฑ…์€ ์ข€๋” ๋Œ€์ค‘์ ์ธ ์„ค๋ช…์„ ํฌํ•จํ•ด์„œ ์žฌ์ถœํŒ ๋˜๋ฉด ์ข‹๊ฒ ๋‹ค.

[์ฑ…] ๋ˆ„๊ฐ€๋” ๋‚˜์œ๊ฐ€? ์นด๊ธธ or ๋ชฌ์‚ฐํ† ?

์„ธ๊ณ„ ์‹๋Ÿ‰ ์‚ฐ์—… ๊ด€๋ จ ๋ญ”๊ฐ€ ์ปค๋‹ค๋ž€ ์Œ๋ชจ๊ฐ€ ์žˆ์ง€์•Š์„๊นŒ, ์ด๋ฆ„์€ ์ƒ๊ฐ ๋‚˜์ง€ ์•Š์ง€๋งŒ ์บ๋‚˜๋‹ค ์‚ฌ๋žŒ์ด ์˜ค๋ž˜์ „ ์“ด ์นด๊ธธ ๊ด€๋ จ ์ฑ…์„ ์ฝ์—ˆ๋Š”๋ฐ... omg ์นด๊ธธ์— ๋Œ€ํ•œ ๋“œ๋ฌธ๋“œ๋ฌธ ๋น„ํŒ์„ ์ œ์™ธํ•˜๋ฉด ์นด๊ธธ์—์„œ ์ผํ•˜๋Š” ์‚ฌ๋žŒ์ด ์“ด ์นด๊ธธ์˜ ๊ธฐ์—… ์—ญ์‚ฌ์ฑ… ๊ฐ™๋‹คใ…‹. ๊ทธ๋งŒํผ ์นด๊ธธ์ด ์ •๋ณด๊ณต๊ฐœ์— ์†Œ๊ทน์ ์ด๋ผ ์ €์ž๊ฐ€ ๋ฐœ๋กœ ๋›ฐ๋ฉฐ ์‚ฌ์‹ค๊ด€๊ณ„๋ฅผ ํŒŒ์•…ํ•œ๊ฑด ์ข‹์€๋ฐ, ๊ฒฐ๊ตญ ์นด๊ธธ ์—ญ์‚ฌ์˜ ๋‚˜์—ด์ด๋ผ ๋„ˆ๋ฌด๋‚˜๋„ ์ง€๋ฃจํ•œ ์ฑ…. ์‚ฌ์„œ๋กœ์„œ ๊ฐ€์น˜๊ฐ€ ์žˆ๋‹ค๊ณ  ํ•ด์•ผํ• ๊นŒ๋‚˜? ๊ทธ๊ฑด ๊ทธ๋ ‡๊ณ  ์š”์ƒˆ ์ง€์นด๋ฐ”์ด๋Ÿฌ์Šค ๊ด€๋ จ ๋ชฌ์‚ฐํ† ์˜ ๋†์•ฝ ๊ด€๋ จ ์Œ๋ชจ๋ก ์ด ๋– ๋Œ๋˜๋ฐ ๋ชฌ์‚ฐํ† ์—๋Š” ๋ญ”๊ฐ€ ์žฌ๋ฏธ๋‚œ ์Œ๋ชจ๊ฐ€ ์žˆ์ง€์•Š์„๊นŒ๋‚˜?

[์ฑ…] ๋ฐฐ์งฑ ๊น€์˜์‚ฌ์˜ ์ƒ๋Œ€์„ฑ ์ด๋ก  by ์•„์ธ์Šˆํƒ€์ธ

์•„์ธ์Šˆํƒ€์ธ์ด ์ง์ ‘ ์“ด - ์‚ฌ์‹ค ๊ทธ์˜ ๊ฐ•์—ฐ์„ ์ฑ…์œผ๋กœ ์—ฎ์€๊ฒƒ - ์ƒ๋Œ€์„ฑ ์ด๋ก ์„ ์ง์ ‘ ๋ณผ์ˆ˜ ์žˆ๋‹ค๋‹ˆ. ๋‰ดํ„ด์ด ์ง์ ‘ ์“ด ํ”„๋ฆฐ์‹œํ”ผ์•„?๋Š” ๋„ˆ๋ฌด ์˜ค๋ž˜๋˜ ์ง€๋ฃจํ• ๊ฒƒ ๊ฐ™๊ณ , ์•„์ธ์Šˆํƒ€์ธ์˜ ์ƒ๋Œ€์„ฑ ์ด๋ก ์ด ๋‚˜์˜จ์ง€ 100๋…„ ์ •๋„๋ฉด ๋™์‹œ๋Œ€์ธ๋ฐ ์—ญ์‚ฌ์  ์ˆœ๊ฐ„์„ ํ•จ๊ป˜ ํ•˜๋Š” ๊ธฐ๋ถ„์ด๋ž„๊นŒ. ๊น€์˜์‚ฌ ๋Œ€๋‹จํ•˜๋‹ค~ ๊ทผ๋Œ€ ๋Œ€ํ•™์›์—์„œ ๋ฏธ์ ๋ถ„ํ•™, ์„ ํ˜•๋Œ€์ˆ˜, ์—ฐ์†์ฒด์—ญํ•™ ๊ณต๋ถ€ํ•œ ๋‚˜๋„ ๋ญ” ๋ง์ธ์ง€ ๋ชจ๋ฅผ ์ •๋„๋กœ ๋ถˆ์นœ์ ˆํ•œ ์ˆ˜์‹์˜ ํ–ฅ์—ฐ. ์ด๋Ÿฐ๊ฑธ ๋Œ€์ค‘์ ์ธ ํ‘œ์ง€ - ๊ฒŒ๋‹ค๊ฐ€ ์„œํ‰๋„ ๋ง๋ฐœ ์ข‹์€ ๋ธŒ๋ผ์ด์–ธ ๊ทธ๋ฆฐ - ๋กœ ์ถœํŒํ•œ ๊น€์˜์‚ฌ ์ •๋ง ๋Œ€๋‹จํ•˜๋‹ค~

gravity and quantum mechanics

hawking radiation

black hole information paradox: contrary to the thermal radiation of a black body (statistical in nature), hawking radiation (early version) contatins no information (black hole has no hair)

AdS/CFT correspondence

Trans-Planckian problem
Hawking's original calculation requires talking about quantum particles in which the wavelength becomes shorter than the Planck length near the black hole's horizon

[์˜ํ™”] dead pool (์•ฝ๊ฐ„์˜ ์Šคํฌ์ผ๋ง)

์ฒ˜์Œ๋ถ€ํ„ฐ ์‹œ๊ฐ„ ์ˆœ์„œ๋Œ€๋กœ ์•”์— ๊ฑธ๋ ค์„œ ์—ฌ์นœ์ด๋ž‘ ์‚ฌ๋ž‘ํ•˜์ง€๋งŒ ํ—ค์–ด์ง€๊ณ  ์–ด์ฉŒ๊ณ  ์ €์ฉŒ๊ณ  ์•ˆํ•ด์„œ ๋„ˆ๋ฌด ์ข‹๋‹ค; ์ฒ˜์Œ๋ถ€ํ„ฐ ์ •์‹ ์—†์ด ์•ก์…˜ ์‹œ์ž‘ํ•˜๋‹ˆ ์ข‹๊ตฌ๋‚˜. ๋ฌผ๋ก  ์ฒ˜์Œ ์•ก์…˜์‹ ์ด ์ตœ๊ณ ์‹ ์ด๋ผ ์ดํ›„ ์ข€ ์•„์‰ฌ์› ์ง€๋งŒ. ๊ฒŒ๋‹ค๊ฐ€ ๊ฒฐ๊ตญ ์•ฝ๊ฐ„์˜ ์•ก์…˜์‹  ์ดํ›„ ์‹ ํŒŒ๊ฐ€ ์ด์–ด์ง€๊ณ ใ…‹. ์–ด๋ฒค์ ธ์Šค์— ๋น„ํ•˜๋ฉด ์™œ ์‹ธ์šฐ๋Š”์ง€ ๋Œ€์˜ ๋นˆ์•ฝํ•˜์ง€๋งŒ ์›๋ž˜ ์บ๋ฆญํ„ฐ๊ฐ€ ๊ทธ๋Ÿฌ๋ ค๋‹ˆใ…‹. 80๋…„๋Œ€ ์‚˜ ์‚ฌ์šด๋“œํŠธ๋ž™ 40,50์‹ญ๋Œ€ ๊ณต๋žตํ•˜๊ธฐ ์ข‹๊ณ ~ ์—ฌ์ฃผ๋Š” ์ด์œ๋ฐ ๋‚˜์ด ๋“ค๋ฉด ์™ ์ง€ ๋งˆ์ดํด์žญ์Šจ ๋‹ฎ์„๊ฒƒ๋งŒ๊ฐ™๋‹ค. ๊ฒฐ๋ก ์€ ์‚ฌ๋ž‘ํ•œ๋‹ค๋ฉด ์†”์งํ•˜๋ผ~~~