Do i imagine the linear (straight line) homotopy in a correct way?












1












$begingroup$


Today i learned about the linear homotopy which says that any two paths $f_0, f_1$ in $mathbb{R}^n$ are homotopic via the homotopy $$ f_t(s) = (1-t)f_0(s) + tf_1(s)$$



Am i right in imagining the given homotopy as something like this?



enter image description here



such that $F(s,t) = f_t(s) $ are simply the linesegments going from $f_0(s)$ towards $f_1(s)$ as the straight lines (which "connect" $f_0$ and $f_1$ for every $sin [0,1]$) as drawn in the picture?



Sorry if this question might be a trivial one, i just want to make sure i don't get things wrong.



Thanks for any kind of feedback!






algebraic-topology homotopy-theory path-connected







share|cite|improve this question









$endgroup$








  • 1




    $begingroup$
    It's correct. Furthermore, any point $s$ moves along its straight line at constant speed.
    $endgroup$
    – Lukas Kofler
    1 hour ago










  • $begingroup$
    isn't the point $t$ rather moving along its straight line? to me, $s$ is the parameter moving along the lines from $x_0$ to $x_1$ whereas $t$ moves along the straight linesegments between $f_0$ and $f_1$
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    That's what I was trying to say, sorry -- a fixed point $f_0(s)$ moves at constant speed as $t$ varies.
    $endgroup$
    – Lukas Kofler
    1 hour ago
















1












$begingroup$


Today i learned about the linear homotopy which says that any two paths $f_0, f_1$ in $mathbb{R}^n$ are homotopic via the homotopy $$ f_t(s) = (1-t)f_0(s) + tf_1(s)$$



Am i right in imagining the given homotopy as something like this?



enter image description here



such that $F(s,t) = f_t(s) $ are simply the linesegments going from $f_0(s)$ towards $f_1(s)$ as the straight lines (which "connect" $f_0$ and $f_1$ for every $sin [0,1]$) as drawn in the picture?



Sorry if this question might be a trivial one, i just want to make sure i don't get things wrong.



Thanks for any kind of feedback!






algebraic-topology homotopy-theory path-connected







share|cite|improve this question









$endgroup$








  • 1




    $begingroup$
    It's correct. Furthermore, any point $s$ moves along its straight line at constant speed.
    $endgroup$
    – Lukas Kofler
    1 hour ago










  • $begingroup$
    isn't the point $t$ rather moving along its straight line? to me, $s$ is the parameter moving along the lines from $x_0$ to $x_1$ whereas $t$ moves along the straight linesegments between $f_0$ and $f_1$
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    That's what I was trying to say, sorry -- a fixed point $f_0(s)$ moves at constant speed as $t$ varies.
    $endgroup$
    – Lukas Kofler
    1 hour ago














1












1








1





$begingroup$


Today i learned about the linear homotopy which says that any two paths $f_0, f_1$ in $mathbb{R}^n$ are homotopic via the homotopy $$ f_t(s) = (1-t)f_0(s) + tf_1(s)$$



Am i right in imagining the given homotopy as something like this?



enter image description here



such that $F(s,t) = f_t(s) $ are simply the linesegments going from $f_0(s)$ towards $f_1(s)$ as the straight lines (which "connect" $f_0$ and $f_1$ for every $sin [0,1]$) as drawn in the picture?



Sorry if this question might be a trivial one, i just want to make sure i don't get things wrong.



Thanks for any kind of feedback!






algebraic-topology homotopy-theory path-connected







share|cite|improve this question









$endgroup$




Today i learned about the linear homotopy which says that any two paths $f_0, f_1$ in $mathbb{R}^n$ are homotopic via the homotopy $$ f_t(s) = (1-t)f_0(s) + tf_1(s)$$



Am i right in imagining the given homotopy as something like this?



enter image description here



such that $F(s,t) = f_t(s) $ are simply the linesegments going from $f_0(s)$ towards $f_1(s)$ as the straight lines (which "connect" $f_0$ and $f_1$ for every $sin [0,1]$) as drawn in the picture?



Sorry if this question might be a trivial one, i just want to make sure i don't get things wrong.



Thanks for any kind of feedback!






algebraic-topology homotopy-theory path-connected




algebraic-topology homotopy-theory path-connected






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked 1 hour ago









ZestZest

301213




301213








  • 1




    $begingroup$
    It's correct. Furthermore, any point $s$ moves along its straight line at constant speed.
    $endgroup$
    – Lukas Kofler
    1 hour ago










  • $begingroup$
    isn't the point $t$ rather moving along its straight line? to me, $s$ is the parameter moving along the lines from $x_0$ to $x_1$ whereas $t$ moves along the straight linesegments between $f_0$ and $f_1$
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    That's what I was trying to say, sorry -- a fixed point $f_0(s)$ moves at constant speed as $t$ varies.
    $endgroup$
    – Lukas Kofler
    1 hour ago














  • 1




    $begingroup$
    It's correct. Furthermore, any point $s$ moves along its straight line at constant speed.
    $endgroup$
    – Lukas Kofler
    1 hour ago










  • $begingroup$
    isn't the point $t$ rather moving along its straight line? to me, $s$ is the parameter moving along the lines from $x_0$ to $x_1$ whereas $t$ moves along the straight linesegments between $f_0$ and $f_1$
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    That's what I was trying to say, sorry -- a fixed point $f_0(s)$ moves at constant speed as $t$ varies.
    $endgroup$
    – Lukas Kofler
    1 hour ago








1




1




$begingroup$
It's correct. Furthermore, any point $s$ moves along its straight line at constant speed.
$endgroup$
– Lukas Kofler
1 hour ago




$begingroup$
It's correct. Furthermore, any point $s$ moves along its straight line at constant speed.
$endgroup$
– Lukas Kofler
1 hour ago












$begingroup$
isn't the point $t$ rather moving along its straight line? to me, $s$ is the parameter moving along the lines from $x_0$ to $x_1$ whereas $t$ moves along the straight linesegments between $f_0$ and $f_1$
$endgroup$
– Zest
1 hour ago




$begingroup$
isn't the point $t$ rather moving along its straight line? to me, $s$ is the parameter moving along the lines from $x_0$ to $x_1$ whereas $t$ moves along the straight linesegments between $f_0$ and $f_1$
$endgroup$
– Zest
1 hour ago




1




1




$begingroup$
That's what I was trying to say, sorry -- a fixed point $f_0(s)$ moves at constant speed as $t$ varies.
$endgroup$
– Lukas Kofler
1 hour ago




$begingroup$
That's what I was trying to say, sorry -- a fixed point $f_0(s)$ moves at constant speed as $t$ varies.
$endgroup$
– Lukas Kofler
1 hour ago










2 Answers
2






active

oldest

votes


















2












$begingroup$

Yes. Perhaps to help you see why this is true, pick an arbitrary $s$ value $bar{s}$ and call $a := f_0(bar{s})$ and $b := f_1(bar{s})$. Examining the homotopy,
$$
H_{bar{s}}(t) := F(bar{s}, t) = a(1-t) + bt
$$



we see that it is the parametric equation of a straight line connecting points $a$ and $b$ in $mathbb{R}^n$. If you draw this line for each $bar{s}$ choice, you get your diagram. Perhaps write a bit of code to construct such a plot?



Furthermore, one may be interested in the "speed" at which $a$ "moves" to $b$. We find it to be a constant,
$$
dfrac{dH_{bar{s}}}{dt} = b - a
$$






share|cite|improve this answer











$endgroup$













  • $begingroup$
    this is very helpful @jnez71. Thanks a lot!
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    No problem! I added a bit more to cover some of the comments about speed
    $endgroup$
    – jnez71
    1 hour ago



















1












$begingroup$

Yes, it is absolutely correct.






share|cite|improve this answer











$endgroup$













  • $begingroup$
    thank you very much @Paul. Just being curious, what does it mean that your answer is "community wiki"?
    $endgroup$
    – Zest
    1 hour ago










  • $begingroup$
    See math.stackexchange.com/help/privileges/edit-community-wiki. A community wiki can be edited by everybody. Frankly, my answer was only a feedback, and I guess you didn't expect more. But of course it doesn't deserve positive reputation.
    $endgroup$
    – Paul Frost
    1 hour ago










  • $begingroup$
    thanks Paul. In fact, your answer was all i was hoping for. Would you mind me accepting @jnez72's answer rather than yours even though both helped me?
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    No problem - it is okay!
    $endgroup$
    – Paul Frost
    1 hour ago










  • $begingroup$
    By the way, in my opinion it is important to make it visible in the question queue that a question has been answered. If you click at "Unanswered" in the upper left corne of this page, you will read something like "248,877 questions with no upvoted or accepted answers ", the number of course growing. If you look at these questions, you will see that a great many are actually answered in comments. If that should happen to one of your questions, do not hesitate to write an answer and acknowledge it.
    $endgroup$
    – Paul Frost
    1 hour ago














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2 Answers
2






active

oldest

votes








2 Answers
2






active

oldest

votes









active

oldest

votes






active

oldest

votes









2












$begingroup$

Yes. Perhaps to help you see why this is true, pick an arbitrary $s$ value $bar{s}$ and call $a := f_0(bar{s})$ and $b := f_1(bar{s})$. Examining the homotopy,
$$
H_{bar{s}}(t) := F(bar{s}, t) = a(1-t) + bt
$$



we see that it is the parametric equation of a straight line connecting points $a$ and $b$ in $mathbb{R}^n$. If you draw this line for each $bar{s}$ choice, you get your diagram. Perhaps write a bit of code to construct such a plot?



Furthermore, one may be interested in the "speed" at which $a$ "moves" to $b$. We find it to be a constant,
$$
dfrac{dH_{bar{s}}}{dt} = b - a
$$






share|cite|improve this answer











$endgroup$













  • $begingroup$
    this is very helpful @jnez71. Thanks a lot!
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    No problem! I added a bit more to cover some of the comments about speed
    $endgroup$
    – jnez71
    1 hour ago
















2












$begingroup$

Yes. Perhaps to help you see why this is true, pick an arbitrary $s$ value $bar{s}$ and call $a := f_0(bar{s})$ and $b := f_1(bar{s})$. Examining the homotopy,
$$
H_{bar{s}}(t) := F(bar{s}, t) = a(1-t) + bt
$$



we see that it is the parametric equation of a straight line connecting points $a$ and $b$ in $mathbb{R}^n$. If you draw this line for each $bar{s}$ choice, you get your diagram. Perhaps write a bit of code to construct such a plot?



Furthermore, one may be interested in the "speed" at which $a$ "moves" to $b$. We find it to be a constant,
$$
dfrac{dH_{bar{s}}}{dt} = b - a
$$






share|cite|improve this answer











$endgroup$













  • $begingroup$
    this is very helpful @jnez71. Thanks a lot!
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    No problem! I added a bit more to cover some of the comments about speed
    $endgroup$
    – jnez71
    1 hour ago














2












2








2





$begingroup$

Yes. Perhaps to help you see why this is true, pick an arbitrary $s$ value $bar{s}$ and call $a := f_0(bar{s})$ and $b := f_1(bar{s})$. Examining the homotopy,
$$
H_{bar{s}}(t) := F(bar{s}, t) = a(1-t) + bt
$$



we see that it is the parametric equation of a straight line connecting points $a$ and $b$ in $mathbb{R}^n$. If you draw this line for each $bar{s}$ choice, you get your diagram. Perhaps write a bit of code to construct such a plot?



Furthermore, one may be interested in the "speed" at which $a$ "moves" to $b$. We find it to be a constant,
$$
dfrac{dH_{bar{s}}}{dt} = b - a
$$






share|cite|improve this answer











$endgroup$



Yes. Perhaps to help you see why this is true, pick an arbitrary $s$ value $bar{s}$ and call $a := f_0(bar{s})$ and $b := f_1(bar{s})$. Examining the homotopy,
$$
H_{bar{s}}(t) := F(bar{s}, t) = a(1-t) + bt
$$



we see that it is the parametric equation of a straight line connecting points $a$ and $b$ in $mathbb{R}^n$. If you draw this line for each $bar{s}$ choice, you get your diagram. Perhaps write a bit of code to construct such a plot?



Furthermore, one may be interested in the "speed" at which $a$ "moves" to $b$. We find it to be a constant,
$$
dfrac{dH_{bar{s}}}{dt} = b - a
$$







share|cite|improve this answer














share|cite|improve this answer



share|cite|improve this answer








edited 1 hour ago

























answered 1 hour ago









jnez71jnez71

2,495720




2,495720












  • $begingroup$
    this is very helpful @jnez71. Thanks a lot!
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    No problem! I added a bit more to cover some of the comments about speed
    $endgroup$
    – jnez71
    1 hour ago


















  • $begingroup$
    this is very helpful @jnez71. Thanks a lot!
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    No problem! I added a bit more to cover some of the comments about speed
    $endgroup$
    – jnez71
    1 hour ago
















$begingroup$
this is very helpful @jnez71. Thanks a lot!
$endgroup$
– Zest
1 hour ago




$begingroup$
this is very helpful @jnez71. Thanks a lot!
$endgroup$
– Zest
1 hour ago




1




1




$begingroup$
No problem! I added a bit more to cover some of the comments about speed
$endgroup$
– jnez71
1 hour ago




$begingroup$
No problem! I added a bit more to cover some of the comments about speed
$endgroup$
– jnez71
1 hour ago











1












$begingroup$

Yes, it is absolutely correct.






share|cite|improve this answer











$endgroup$













  • $begingroup$
    thank you very much @Paul. Just being curious, what does it mean that your answer is "community wiki"?
    $endgroup$
    – Zest
    1 hour ago










  • $begingroup$
    See math.stackexchange.com/help/privileges/edit-community-wiki. A community wiki can be edited by everybody. Frankly, my answer was only a feedback, and I guess you didn't expect more. But of course it doesn't deserve positive reputation.
    $endgroup$
    – Paul Frost
    1 hour ago










  • $begingroup$
    thanks Paul. In fact, your answer was all i was hoping for. Would you mind me accepting @jnez72's answer rather than yours even though both helped me?
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    No problem - it is okay!
    $endgroup$
    – Paul Frost
    1 hour ago










  • $begingroup$
    By the way, in my opinion it is important to make it visible in the question queue that a question has been answered. If you click at "Unanswered" in the upper left corne of this page, you will read something like "248,877 questions with no upvoted or accepted answers ", the number of course growing. If you look at these questions, you will see that a great many are actually answered in comments. If that should happen to one of your questions, do not hesitate to write an answer and acknowledge it.
    $endgroup$
    – Paul Frost
    1 hour ago


















1












$begingroup$

Yes, it is absolutely correct.






share|cite|improve this answer











$endgroup$













  • $begingroup$
    thank you very much @Paul. Just being curious, what does it mean that your answer is "community wiki"?
    $endgroup$
    – Zest
    1 hour ago










  • $begingroup$
    See math.stackexchange.com/help/privileges/edit-community-wiki. A community wiki can be edited by everybody. Frankly, my answer was only a feedback, and I guess you didn't expect more. But of course it doesn't deserve positive reputation.
    $endgroup$
    – Paul Frost
    1 hour ago










  • $begingroup$
    thanks Paul. In fact, your answer was all i was hoping for. Would you mind me accepting @jnez72's answer rather than yours even though both helped me?
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    No problem - it is okay!
    $endgroup$
    – Paul Frost
    1 hour ago










  • $begingroup$
    By the way, in my opinion it is important to make it visible in the question queue that a question has been answered. If you click at "Unanswered" in the upper left corne of this page, you will read something like "248,877 questions with no upvoted or accepted answers ", the number of course growing. If you look at these questions, you will see that a great many are actually answered in comments. If that should happen to one of your questions, do not hesitate to write an answer and acknowledge it.
    $endgroup$
    – Paul Frost
    1 hour ago
















1












1








1





$begingroup$

Yes, it is absolutely correct.






share|cite|improve this answer











$endgroup$



Yes, it is absolutely correct.







share|cite|improve this answer














share|cite|improve this answer



share|cite|improve this answer








answered 1 hour ago


























community wiki





Paul Frost













  • $begingroup$
    thank you very much @Paul. Just being curious, what does it mean that your answer is "community wiki"?
    $endgroup$
    – Zest
    1 hour ago










  • $begingroup$
    See math.stackexchange.com/help/privileges/edit-community-wiki. A community wiki can be edited by everybody. Frankly, my answer was only a feedback, and I guess you didn't expect more. But of course it doesn't deserve positive reputation.
    $endgroup$
    – Paul Frost
    1 hour ago










  • $begingroup$
    thanks Paul. In fact, your answer was all i was hoping for. Would you mind me accepting @jnez72's answer rather than yours even though both helped me?
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    No problem - it is okay!
    $endgroup$
    – Paul Frost
    1 hour ago










  • $begingroup$
    By the way, in my opinion it is important to make it visible in the question queue that a question has been answered. If you click at "Unanswered" in the upper left corne of this page, you will read something like "248,877 questions with no upvoted or accepted answers ", the number of course growing. If you look at these questions, you will see that a great many are actually answered in comments. If that should happen to one of your questions, do not hesitate to write an answer and acknowledge it.
    $endgroup$
    – Paul Frost
    1 hour ago




















  • $begingroup$
    thank you very much @Paul. Just being curious, what does it mean that your answer is "community wiki"?
    $endgroup$
    – Zest
    1 hour ago










  • $begingroup$
    See math.stackexchange.com/help/privileges/edit-community-wiki. A community wiki can be edited by everybody. Frankly, my answer was only a feedback, and I guess you didn't expect more. But of course it doesn't deserve positive reputation.
    $endgroup$
    – Paul Frost
    1 hour ago










  • $begingroup$
    thanks Paul. In fact, your answer was all i was hoping for. Would you mind me accepting @jnez72's answer rather than yours even though both helped me?
    $endgroup$
    – Zest
    1 hour ago






  • 1




    $begingroup$
    No problem - it is okay!
    $endgroup$
    – Paul Frost
    1 hour ago










  • $begingroup$
    By the way, in my opinion it is important to make it visible in the question queue that a question has been answered. If you click at "Unanswered" in the upper left corne of this page, you will read something like "248,877 questions with no upvoted or accepted answers ", the number of course growing. If you look at these questions, you will see that a great many are actually answered in comments. If that should happen to one of your questions, do not hesitate to write an answer and acknowledge it.
    $endgroup$
    – Paul Frost
    1 hour ago


















$begingroup$
thank you very much @Paul. Just being curious, what does it mean that your answer is "community wiki"?
$endgroup$
– Zest
1 hour ago




$begingroup$
thank you very much @Paul. Just being curious, what does it mean that your answer is "community wiki"?
$endgroup$
– Zest
1 hour ago












$begingroup$
See math.stackexchange.com/help/privileges/edit-community-wiki. A community wiki can be edited by everybody. Frankly, my answer was only a feedback, and I guess you didn't expect more. But of course it doesn't deserve positive reputation.
$endgroup$
– Paul Frost
1 hour ago




$begingroup$
See math.stackexchange.com/help/privileges/edit-community-wiki. A community wiki can be edited by everybody. Frankly, my answer was only a feedback, and I guess you didn't expect more. But of course it doesn't deserve positive reputation.
$endgroup$
– Paul Frost
1 hour ago












$begingroup$
thanks Paul. In fact, your answer was all i was hoping for. Would you mind me accepting @jnez72's answer rather than yours even though both helped me?
$endgroup$
– Zest
1 hour ago




$begingroup$
thanks Paul. In fact, your answer was all i was hoping for. Would you mind me accepting @jnez72's answer rather than yours even though both helped me?
$endgroup$
– Zest
1 hour ago




1




1




$begingroup$
No problem - it is okay!
$endgroup$
– Paul Frost
1 hour ago




$begingroup$
No problem - it is okay!
$endgroup$
– Paul Frost
1 hour ago












$begingroup$
By the way, in my opinion it is important to make it visible in the question queue that a question has been answered. If you click at "Unanswered" in the upper left corne of this page, you will read something like "248,877 questions with no upvoted or accepted answers ", the number of course growing. If you look at these questions, you will see that a great many are actually answered in comments. If that should happen to one of your questions, do not hesitate to write an answer and acknowledge it.
$endgroup$
– Paul Frost
1 hour ago






$begingroup$
By the way, in my opinion it is important to make it visible in the question queue that a question has been answered. If you click at "Unanswered" in the upper left corne of this page, you will read something like "248,877 questions with no upvoted or accepted answers ", the number of course growing. If you look at these questions, you will see that a great many are actually answered in comments. If that should happen to one of your questions, do not hesitate to write an answer and acknowledge it.
$endgroup$
– Paul Frost
1 hour ago




















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數位音樂下載

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數位音樂下載 為非以「實體」方式來販賣音樂的相關產品，而使用數位格式如mp3、AAC等文件格式來進行銷售販賣的一种音乐产业形式。著名的數位音樂下載服務商有iTunes Store、RecoChoku、Google Play音乐和微软Zune等。数字音乐下载在二十一世纪初一度风靡全球， [1] [2] 使得传统唱片产业走向衰落，但其自身也在2010年代流媒体音乐服务如Apple Music、Spotify等的挤压下迅速失去市场份额。 [3] [4] 数字音乐下载有便于携带、传播迅速、制作简单成本低等优点，与流媒体音乐相比也能更好保障音乐人权益； [5] 但它同时很可能带来侵犯版权和滥用的情形， [6] 也给音乐产业带来了诸多不利影响。数字音乐下载为音乐人和乐迷提供了更加便捷直接的交流渠道，也一定程度上推动了网络音乐人的出现和独立音乐的迅速发展。 [7] 目录 1 历史 1.1 技术积淀（1987-2000） 1.2 出现与兴起（2000-2004） 1.3 唱片市场的颠覆者（2004-2007） 1.4 巅峰和衰落（2005-2013） 1.5 摇摇欲坠的现状与不可预知的明天（2014至今） 2 主要文件格式 2.1 PCM编码格式 2.1.1 WAV 2.1.2 APE 2.1.3 FLAC 2.2 苹果推出的无损文件格式 2.2.1 AIFF 2.2.2 ALAC 2.3 有损压缩格式 2.3.1 MP3 2.3.2 AAC 3 主要市场 3.1 iTunes Store 3.2 Google Play音乐商店 3.3 亚马逊音乐商店 3.4 部分其他音乐商店 4 影响与评价 4.1 对音乐产业的影响 4.2 对科技行业的影响 4.3 正面评价 4.4 负面评价 4.4.1 侵权问题 4.4.2 经营模式不明晰 4.4.3 不适应移动时代 4.5 文化现象 5 延伸阅读 6 参考资料 历史 苹果iTunes+iPod的软硬件搭配让数字音...
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When can things happen in Etherscan, such as the picture below?

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2 I don't know why balance of the address is 0. when can this situation? etherscan balances share | improve this question asked yesterday Ru Hi Ru Hi 11 1 New contributor Ru Hi is a new contributor to this site. Take care in asking for clarification, commenting, and answering. Check out our Code of Conduct. add a comment  |  ...
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格利澤436b

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格利泽436b 太陽系外行星 太陽系外行星列表 艺术家笔下的格利泽436b 母恆星 母恆星 Gliese 436 星座 獅子座 赤經 ( α ) 11 h  42 m  11.0941 s [1] 赤緯 ( δ ) +26° 42′ 23.652″ [1] 距離 33.4 ly (10.2 pc) 光譜類型 M2.5 V [1] 軌道參數 半长轴 ( a ) 0.0291±0.0004 [2] AU 軌道離心率 ( e ) 0.150±0.012 [2] 公轉週期 ( P ) 2.643904±0.000005 [3] d (0.00723849 y) 軌道傾角 ( i ) 85.8 +0.21 −0.25 [3] ° 角距 ( θ ) 2.794 mas 近星點時間 ( T 0 ) 2,451,551.716 ±0.01 JD 半振幅 ( K ) 18.68±0.8 m/s 物理性质 质量 ( m ) 22.2±1.0 [2] M ⊕ 半徑 ( r ) 4.327±0.183 [2] [4] R ⊕ 密度 ( ρ ) 1.51 g cm -3 表面重力 ( g ) 1.18 g 溫度 ( T ) 712±36 [2] K 發現 發現時間 2004 發現者 巴特勒、沃格特、 馬西 et al. 發現方法 徑向速度、凌日法 發現地點 美國加利福尼亞州 發表論文 出版 其他名稱 Ross 905 b, GJ 436 b, [5] LTT 13213 b, GCTP 2704.10 b, LHS 310, AC+27:28217 b, Vyssotsky 616 b, HIP 57087 b, GEN# +9.80120068 b, LP 319-75 b, G 121-7 b, LSPM J1142+2642 b, 1RXS J114211.9+264328 b, ASCC 683818 b, G 147-68 b, UCAC2 41198281 b, BP...
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