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  • 检验假设

    A signpost with two arrows labeled 'Wrong Way' and 'Right Way'.

    How can I show that my hypothesis is wrong?
    ::我怎么能证明我的假设是错误的呢?

    Many young scientists learn that a good scientist tries to disprove their  hypothesis . This is the best way to be sure that your hypothesis is getting a rigorous test. Why do you think established scientists tell students this? Why is it a good idea?
    ::许多年轻的科学家知道,一个优秀的科学家试图反驳他们的假设。这是确保你的假设得到严格检验的最佳方法。你认为,老科学家为什么要告诉学生这一点?为什么这是个好主意?

    Testing Hypotheses
    ::测试假假设

    How do you test a hypothesis? Often you need scientific tools, perhaps a microscope or a  magnetometer . You need to know how to analyze the  data  that comes from those tools. Often computers are needed to gather, analyze, and interpret the data.
    ::您如何测试假设? 您通常需要科学工具, 也许是显微镜或磁强计。 您需要知道如何分析来自这些工具的数据。 通常需要计算机来收集、 分析和解释数据 。

    In this example, we will look into the scientific literature to find data. These studies were done using the  . The scientists used the necessary tools and computers. To test a new hypothesis, we would need to do the  experiments  ourselves.
    ::在这个例子中,我们将研究科学文献以寻找数据。这些研究是使用这些仪器进行的。科学家们使用了必要的工具和计算机。为了测试一个新的假设,我们需要自己做实验。

    We will test the two hypothesis that we developed to explain this  fact : Atmospheric CO 2  has increased over the past five decades.
    ::我们将检验我们为解释这一事实而提出的两个假设:大气二氧化碳在过去五十年中有所增加。

    Testing Hypothesis 1
    ::测试假假设1

    Hypothesis 1: Atmospheric CO 2  has increased over the past five decades because the amount of CO 2  gas released by   has increased.
    ::假设1:大气CO2在过去五十年中有所增加,因为排放的CO2气体数量有所增加。

    To test Hypothesis 1, we need to see if the amount of CO 2  gas released by volcanoes over the past several decades has increased.
    ::为了测试假想1,我们需要看看过去几十年火山释放的二氧化碳气体是否有所增加。

    There are two ways volcanoes could account for the increase in CO 2 :
    ::火山有两种方法可以解释二氧化碳增加的原因:

    • There has been an increase in volcanic eruptions in that time.
      ::当时火山爆发有所增加。
    • The CO 2  content of volcanic gases has increased over time.
      ::火山气体的CO2含量随着时间推移而增加。

    Our research tells us that 50-70 eruptions occur every  year . We see that the number of volcanic eruptions is about constant. We learn from different scientific papers that volcanic gas compositions have not changed over time. Different   have different gas compositions. However, the overall the gases are the same. Another scientific paper states that major volcanic eruptions for the past 30 years have caused short-term cooling, not warming!
    ::我们的研究告诉我们,每年有50-70次火山爆发。我们看到火山爆发的数量是恒定的。我们从不同的科学论文中了解到,火山气体的构成在一段时间内没有变化。不同的气体构成是不同的。然而,气体的构成是相同的。另一个科学论文指出,过去30年中爆发的大型火山爆发造成了短期冷却,而不是变暖!

    Hypothesis 1 is wrong! Volcanic activity is not able to account for the rise in atmospheric CO 2 . Remember that  science  is  falsifiable . We can discard Hypothesis 1.
    ::假设1是错误的! 火山活动无法解释大气中二氧化碳的上升。 记住科学是可变的。 我们可以丢弃假设1。

    When a hypothesis is wrong, often much has been learned anyway. Rarely is the pursuit of a hypothesis a total loss!
    ::当假说是错误的时,往往已经学到很多东西。 追求假说很少是完全的损失!

    Testing Hypothesis 2
    ::测试假设2

    Hypothesis 2: The increase in atmospheric CO 2  is due to the increase in the amount of  fossil fuels  that are being burned.
    ::假设2:大气CO2的增加是由于燃烧的矿物燃料量的增加。

    To test hypothesis 2, we need to see if the amount of CO 2  gas released by fossil fuels over the past several decades has increased. We look into the scientific literature and find the following graph ( Figure   ).
    ::要检验假设2,我们需要看看化石燃料在过去几十年中释放的二氧化碳气体数量是否有所增加。 我们查看科学文献并找到下图(图 ) 。

    Graph showing global CO2 emissions from fossil fuels and cement production from 1750 to 2010.
     
    Global carbon dioxide emissions from fossil fuel consumption and cement production. The black line represents all emission types combined. The colored lines show emissions from individual fossil fuels.

    Fossil fuels have added an increasing amount of carbon dioxide to the  atmosphere  since the beginning of the  Industrial Revolution  in the mid-19th century. Hypothesis 2 appears to be at least partly true!
    ::自19世纪中叶工业革命开始以来,化石燃料给大气增加了越来越多的二氧化碳。 假说2至少部分是真实的!

    It is very important when testing hypotheses to eliminate any bias. A biased researcher may miss important factors that do not match their bias. It actually is good to try to disprove your own hypothesis! Having other researchers involved will also help to eliminate bias.
    ::当测试假设以消除任何偏见时,这一点非常重要。 有偏见的研究人员可能会忽略与其偏见不相符的重要因素。 试图反驳自己的假设是件好事。 吸收其他研究人员参与也将有助于消除偏见。

    Summary
    ::摘要

    • Science is falsifiable. An incorrect hypothesis is discarded.
      ::科学是伪造的 错误的假设被抛弃了
    • Carbon dioxide levels in the atmosphere are increasing. Fossil fuel burning is increasing. The rise in fossil fuel burning is increasing the CO 2  in the atmosphere.
      ::大气中的二氧化碳含量正在上升,化石燃料燃烧正在增加,化石燃料燃烧的增加正在增加大气中的二氧化碳含量。
    • More than one hypothesis can be tested at a time. This is called multiple working hypotheses.
      ::一次可以测试不止一种假设。 这叫做多重工作假设。

    Review
    ::回顾

    1. Could there be other reasons that CO 2  has been increasing in the atmosphere for the past several decades? Could there be more than one reason?
      ::在过去几十年中,大气层中的二氧化碳是否还存在其他原因? 是否不止一个原因?
    1. At this moment, can we say that the increase in fossil fuel burning is causing the increase in CO 2  in the atmosphere?
      ::此时此刻,我们能否说化石燃料燃烧的增加正在导致大气中的二氧化碳增加?
    1. At this moment, can we say that the increase in fossil fuel burning is causing the rise in average global temperature?
      ::此时此刻,我们能否说化石燃料燃烧的增加正在导致全球平均气温上升?
    1. What do we need to do next to address the last two questions?
      ::接下来,为了解决最后两个问题,我们需要做些什么?

    Explore More
    ::探索更多

    Use the resource below to answer the questions that follow.
    ::利用以下资源回答以下问题。

     

     

    1. How are they using the word "theory" in this video? What word would be more accurate for them to use in this context?
      ::这段影片中他们如何使用“理论”一词?
    1. What is the hypothesis they are testing?
      ::他们测试的假设是什么?
    1. How do they test the hypothesis?
      ::他们如何检验假设?
    1. What were their results?
      ::其结果如何?
    1. Is their hypothesis absolutely, certainly correct? If so, explain your reasoning. If not, what can they do to further narrow down whether the hypothesis is correct?
      ::他们的假设是否绝对正确?如果正确,请解释一下你的推理。如果不正确,他们能做些什么来进一步缩小假设是否正确?