Probability of two things happening at the same time

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Discussion Overview

The discussion revolves around the probability of multiple events occurring simultaneously, specifically focusing on scenarios such as two or three arrows hitting a target at the exact same time. The conversation explores theoretical implications of probability in continuous distributions and the nature of simultaneous events.

Discussion Character

  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant suggests that with an infinite number of time frames, the probability of two events happening at the exact same time could be considered one in infinity.
  • Another participant argues that both probabilities are zero, implying that simultaneous occurrences in a continuous distribution have no meaningful probability.
  • Some participants question the possibility of two arrows hitting a target simultaneously, indicating a belief that it is feasible despite the probability being zero.
  • It is noted that while events may be possible, they can still have a zero probability, as exemplified by the weight of individuals in a continuous distribution.
  • A participant clarifies that while the target has a nonzero size, the probability of two or three arrows hitting the same point at the same time remains zero.
  • There is a reiteration that the requirement is for arrows to hit the target at the exact same time, which leads to a consensus that the probability is zero.

Areas of Agreement / Disagreement

Participants express disagreement on the interpretation of simultaneous events and their probabilities, with some asserting that the probability is zero while others explore the implications of infinite time frames. The discussion remains unresolved regarding the conceptual understanding of simultaneous occurrences in probability.

Contextual Notes

The discussion highlights limitations in understanding probabilities in continuous distributions and the implications of defining simultaneous events. There is an ongoing exploration of how these concepts apply to practical scenarios.

Dr Chaos
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As there are an infinite number of time frames, does that mean that the probability of two things happening at the exact same time is one in infinity? (For example, two arrows hitting a target simultaneously).

If so, what is the probability of three things happening at the same time? Less than one in infinity?
 
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You are making things needlessly complicated. Both probabilities are 0.
 
But surely it is possible for two arrows to hit a target at once?
 
Things that are possible may have zero probability. For example, everyone has a weight, but the probability that your weight is exactly a given value is zero. The point being if you are selecting from a continuous distribution, any given choice has a zero probability - you can only meaningfully talk about probability of a value in some interval.
 
mathman said:
Things that are possible may have zero probability. For example, everyone has a weight, but the probability that your weight is exactly a given value is zero. The point being if you are selecting from a continuous distribution, any given choice has a zero probability - you can only meaningfully talk about probability of a value in some interval.

So does that mean that the probability of two arrows hitting a target at once is the same as with three?
 
Dr Chaos said:
So does that mean that the probability of two arrows hitting a target at once is the same as with three?

A target has nonzero size, so no. But two arrows and three arrows would (under that model, at least) have probability 0 to hit the same point.
 
CRGreathouse said:
A target has nonzero size, so no. But two arrows and three arrows would (under that model, at least) have probability 0 to hit the same point.

They don't have to hit the same point on the target - they just have to hit it at the exact same time.
 
Dr Chaos said:
They don't have to hit the same point on the target - they just have to hit it at the exact same time.

Then yes, probability 0.
 

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