What Does the h Subscript 70 to the Power of 3 Mean in Supernova Units?

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In summary, units play a crucial role in scientific research by providing a common language for communication and ensuring accuracy and reproducibility of results. SI units are internationally recognized and based on the metric system, while imperial units are primarily used in the United States. Different units should not be used in the same calculation, and conversion between units should be done using specific conversion factors or equations. Omitting or using incorrect units in a scientific study can lead to inaccurate results and conclusions, highlighting the importance of properly labeling and checking units in experimental data.
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resurgance2001
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Hi
This is a really basic question about units. I have been reading a paper about supernova rates and the units are given as:

SN rate per yr MPC^3. h_70^3 (10^ -4)

Could someone tell me what the h subscript 70 to the power of 3 means?

Thanks
 
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It is a dimensionless number denoting the current rate of expansion. It is equal to the current Hubble rate divided by 70 km/s/Mpc.
 
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To the power of 3?
 
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Thanks
 
  • #5
A dimension is just another reference frame
 

What is the importance of units in scientific research?

Units are crucial in scientific research because they provide a common language for communicating and comparing measurements. They also ensure accuracy and precision in experimental data, and allow for reproducibility of results.

What is the difference between SI units and imperial units?

SI (Systeme International) units are the internationally recognized system of measurement used in scientific research, while imperial units are primarily used in the United States. SI units are based on the metric system and are more consistent and easier to convert between different units.

Can different units be used in the same calculation?

No, different units should not be used in the same calculation. In order to perform accurate calculations, all units involved should be in the same system and properly converted if necessary.

How do I convert between different units?

To convert between units, use conversion factors or conversion equations specific to the units being converted. It is important to pay attention to the direction of the conversion and to properly cancel out units to ensure accuracy.

What happens if units are omitted or incorrect in a scientific study?

Omitting or using incorrect units in a scientific study can lead to inaccurate results and conclusions. It is important to always double check and properly label all units in experimental data to ensure the validity and reliability of research findings.

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