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บรรทัด 153:
อย่างไรก็ตามก็ยังไม่มีการสำรวจ รังสีฮอคกิ้งที่หลุมดำใด ๆ
==ผลของการตกลงไปในหลุมดำ==
ในส่วนนี้จะเป็นการอธิบายว่าจะเกิดอะไรขึ้นถ้ามีบางสิ่งตกลงไปในหลุมดำชวาร์สชิลด์ ที่เป็นเป็นไม่หมุนและไม่มีประจุ ส่วนหลุมดำที่หมุนและมีประจุจะมีความยุ่งยากที่เพิ่มขึ้นมาเมื่อตกลงไป ซึ่งจะไม่อธิบายในส่วนนั้น
===Spaghettification===
{{main|spaghettification}}
วัตถุที่อยู่ภายใต้แรงดึงดูดขนาดใหญ่จะสัมผัสได้ถึงแรงที่ขึ้น ๆ ลง ๆ ([[tidal force]]) ที่ทำให้มันไปในทิศทางของวัตถุที่ก่อให้เกิดสนามโน้มถ่วง นี่อาจจะเกิดจาก [[inverse square law]] ทำให้ส่วนที่ใกล้กว่าของวัตถุที่ถูกแผ่ออกสัมผัสกับแรงดึงดูดได้เร็วกว่าส่วนที่อยู่ไกลกว่า ใกล้ ๆ กับหลุมดำ tidal force จะถูกคาดหวังว่าจะเพียงพอที่จะทำให้วัตถุตกลงไป ไม่ว่าจะเป็นอะตอม หรือนิวคลีออน เรียกปรากฏการณ์นี้ว่า[[spaghettification]] กระบวนการSpaghettification นี้จะเริ่มจากวัตถุที่ตกลงไปในหลุมดำจะแยกเป็นสองส่วน และจากนั้นแต่ละส่วนก็จะแยกออกเป็นอีกสองส่วนรวมเป็นสี่ แล้วก็แยกเป็นแปด กระบวนการแยกออกเป็นสองนี้ [[bifurcation]] จะดำิิเินินไปเรื่อย ๆ และผ่านจุดที่จะแยกวัตถุต้นแบบในระดับอะตอม และสุดท้ายกระบวนการนี้จะทำให้วัตถุกลายเป็นสตริงของอนุภาคพื้นฐาน [[elementary particles]].
The strength of the tidal force of a black hole depends on how gravitational attraction changes with distance, rather than on the absolute force being felt. This means that small black holes cause spaghettification while infalling objects are still outside their event horizons, whereas objects falling into large, supermassive black holes may not be deformed or otherwise feel excessively large forces before passing the event horizon.
===Before the falling object crosses the event horizon===
An object in a gravitational field experiences a slowing down of [[time]], called [[gravitational time dilation]], relative to observers outside the field. The outside observer will see that physical processes in the object, including clocks, appear to run slowly. As a test object approaches the event horizon, its gravitational time dilation (as measured by an observer far from the hole) would approach infinity. Its time would appear to be stopped.
From the viewpoint of a distant observer, an object falling into a black hole appears to slow down, approaching but never quite reaching the event horizon: and it appears to become redder and dimmer, because of the extreme [[gravitational red shift]] caused by the gravity of the black hole. Eventually, the falling object becomes so dim that it can no longer be seen, at a point just before it reaches the event horizon. All of this is a consequence of time dilation: the object's movement is one of the processes that appear to run slower and slower, and the time dilation effect is more significant than the acceleration due to gravity; the [[frequency]] of light from the object appears to decrease, making it look redder, because the light appears to complete fewer cycles per "tick" of the ''observer's'' clock; lower-frequency light has less energy and therefore appears dimmer, as well as redder.
From the viewpoint of the falling object, distant objects generally appear [[Blue shift|blue-shifted]] due to the gravitational field of the black hole. This effect may be partly (or even entirely) negated by the [[Redshift|red shift]] caused by the velocity of the infalling object with respect to the object in the distance.
===As the object passes through the event horizon===
From the viewpoint of the falling object, nothing particularly special happens at the event horizon. In fact, there is no (local) way for him to find out whether he has passed the horizon or not. An infalling object takes a finite [[proper time]] (i.e. measured by its own clock) to fall past the event horizon. This in contrast with the infinite amount of time it takes for a distant observer to see the infalling object cross the horizon.
===Inside the event horizon===
The object reaches the singularity at the center within a finite amount of [[proper time]], as measured by the falling object. An observer on the falling object would continue to see objects outside the event horizon, [[Blue shift|blue-shifted]] or [[Redshift|red-shifted]] depending on the falling object's trajectory.
The amount of proper time a faller experiences below the event horizon depends upon where they started from rest, with the maximum being for someone who starts from rest at the event horizon. A paper in 2007 examined the effect of firing a rocket pack within the black hole, showing that this can only reduce the proper time of a person who starts from rest at the event horizon. However, for anyone else, a judicious burst of the rocket can extend the lifetime of the faller, but overdoing it will again reduce the proper time experienced. However, this cannot prevent the inevitable collision with the central singularity.<ref>{{
cite journal
|url=http://adsabs.harvard.edu/abs/2007PASA...24...46L
|author=Lewis, G. F. and Kwan, J.
|year=2007
|title=No Way Back: Maximizing Survival Time Below the Schwarzschild Event Horizon
|journal=Publications of the Astronomical Society of Australia
|volume=24
|issue=2
|pages=46-52
}}</ref>
===Hitting the singularity===
As an infalling object approaches the singularity, [[tidal force]]s acting on it approach infinity. All components of the object, including [[atom]]s and [[subatomic particles]], are torn away from each other before striking the singularity. At the singularity itself, effects are unknown; it is believed that a theory of [[quantum gravity]] is needed to accurately describe events near it.<!-- Regardless, as soon as an object passes within the hole's event horizon, it is lost to the outside universe. An observer far from the hole simply sees the hole's mass, charge, and angular momentum change slightly, to reflect the addition of the infalling object's matter. After the event horizon all is unknown. Anything that passes this point cannot be retrieved to study. -- commented out since nothing "passes within the hole's event horizon and lost to the outside universe" in finite time as outside universe sees it. For outside universe, a rock thrown into the hole one million years ago is still outside of the horizon and, theoretically, can be retrieved. -->
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