Talk:Acceleration (special relativity)

Parse error

I'm not sure if this is a general problem or it is on my firefox browser. Many Latex formula show parsing error like this:

Failed to parse (unknown function "\begin"): \begin{array}{c|c} \begin{aligned}\mathbf{r}' & =\mathbf{r}+\mathbf{v}\left[\frac{\mathbf{r\cdot v}}{v^{2}}\left(\gamma_{v}-1\right)-t\gamma_{v}\right]\\ t^{\prime} & =\gamma_{v}\left(t-\frac{\mathbf{r\cdot v}}{c^{2}}\right) \end{aligned} & \begin{aligned}\mathbf{r} & =\mathbf{r}'+\mathbf{v}\left[\frac{\mathbf{r'\cdot v}}{v^{2}}\left(\gamma_{v}-1\right)+t'\gamma_{v}\right]\\ t & =\gamma_{v}\left(t'+\frac{\mathbf{r'\cdot v}}{c^{2}}\right) \end{aligned} \end{array}

--Almuhammedi (talk) 13:16, 4 April 2017 (UTC)

Yes. For now you can go to your Preferences, tab Appearance, bottom section Math, and select option MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools). The errors go away. - DVdm (talk) 13:32, 4 April 2017 (UTC)

Note: when all instances of the string \begin{aligned} resp. \end{aligned} are replaced with \begin{align} resp. \end{align}, the problem goes away.  Done: [1]. - DVdm (talk) 13:45, 4 April 2017 (UTC)

@D.H: you might be interested to see this - Cheers. - DVdm (talk) 14:02, 4 April 2017 (UTC)

I wasn't aware of this problem. Thanks for correcting it, cheers. --D.H (talk) 06:36, 5 April 2017 (UTC)

Consider a simplified overview for the general public; as currently written, only physics majors can easily understand this

A general suggestion is that physics topics include a simplified summary for people unfamiliar with Minkowski space, energy-momentum tensor, hyperbolic motion, Rindler coordinates or Born coordinates. Use of these terms in the introduction is intimidating to the general public, which might include high school students, science fiction writers, or the curious from outside the physics department. That is, consider adding a section like this:

Simplified overview

Straight line acceleration in Newtonian dynamics is calculated by net force divided by mass, or a = F/m, and is the same to an observer as to the object being accelerated. This equation comes from the idea that force changes momentum over time according to F = d(mv)/dt. This gives F=ma when mass is constant and acceleration a = dv/dt. The resulting velocity gain is the acceleration multiplied by time, or v=at.

Special relativity tells us that the accelerated traveler and the still observer measure time differently, by the factor (1-v²/c²)^1/2, where c is the speed of light. This change in how time is measured causes a difference between the acceleration felt by the traveler a’ and the acceleration viewed by the still observer. The traveler might experience an acceleration a’, but the still observer sees the acceleration as a lesser value, which goes to zero as velocity approaches light speed. The relation for straight line travel is:

a = a’ (1-v²/c²)^3/2

This relation can be derived by differentiating F = d(mv)/dt using the substitutions that a = dv/dt, a’=F/m_o and mv = m_ov/(1-v²/c²)^1/2, where m_o is the rest mass, or mass as measured when velocity is zero.

2601:648:8780:79D0:2991:6ABA:33FB:6C0B (talk) 19:26, 30 July 2020 (UTC) Ralph Berger

Unless this is supported by a wp:reliable source, it cannot be taken on board. Is there a textbook that can be used as a source? - DVdm (talk) 19:33, 30 July 2020 (UTC)