シャドーイング練習: Every Way Time Travel Could Work Explained in 9 Minutes - 動画で英語スピーキングを学ぶ
練習モードを選ぶ
各モードは全画面の練習ルームで開きます。
160 文
文が短すぎたり長すぎる場合は、Editをタップして調整してください。
1
Speed time dilation.
2
Imagine two identical twins.
3
One remains on Earth, while the other boards a spacecraft traveling at 99 % of light speed.
4
For every year experienced by the astronaut, roughly seven years pass on Earth.
5
When the astronaut returns, they are genuinely younger than their twin.
6
This happens because time does not pass at the same rate for objects moving at different speeds.
7
The faster you travel, the more slowly your time passes compared with someone who remains behind.
8
A traveler could therefore reach Earth's distant future
9
while aging by only a few decades
10
but instead of pushing the spacecraft close to the speed of
11
light you could make it orbit something with extremely powerful gravity
12
this is gravitational time travel imagine the same twins again one remains on earth
13
while the other orbits close to a supermassive black hole the black hole's gravity bends the space
14
and time surrounding it the closer the spacecraft moves towards it
15
the more slowly time passes inside the ship compared with the
16
twin farther away the astronaut would still feel completely normal their clock heartbeat
17
and aging would continue at the usual rate from their own point of view.
18
But after leaving the black hole and returning, they could discover that decades had passed for their twin, while they had experienced only months.
19
This happens because gravity does more than pull objects towards the black hole.
20
It also bends time around it.
21
Think of space -time like a stretched sheet.
22
Place something extremely heavy in the middle, and the sheet sinks into a deep dip.
23
The closer the spacecraft moves towards it, the deeper it travels into this warped region.
24
But what if we slow down the traveler instead?
25
This leads to the next method, suspended animation.
26
Instead of slowing time, we slow your body so you experience almost none of it.
27
This method would require your body temperature to be lowered, your heartbeat reduced, and the chemical reactions inside your cells slowed to a crawl.
28
With your body using far less energy, it could remain preserved for much longer than an awake human could survive.
29
Think of it like placing food inside a freezer.
30
The freezer does not stop time, but it slows the processes that cause the food to decay.
31
You could enter a chamber, remain unconscious for decades, and wake up having barely experienced the journey.
32
But this is not true time travel.
33
Time outside the chamber continues normally, and your body is still physically present for every year that passes.
34
The method only allows you to skip the waiting.
35
The problem is that human cells are easily damaged by extreme cold, ice formation, and long periods without normal circulation.
36
But this method only lets you travel forward in time.
37
To travel backwards, you would need a shortcut that connects two different moments in time.
38
That leads to the first method capable of reaching the past.
39
Wormhole time travel.
40
Imagine drawing two points on a sheet of paper.
41
One represents Earth today, while the other represents Earth 10 years ago.
42
Normally, there is no path between them, but if space -time could fold until those two points touched, a tunnel could connect them directly.
43
You could enter one side in the present, travel through the shortcut, and leave through the other side in the past.
44
The problem is keeping that path open.
45
Gravity would normally crush the tunnel shut before anything could pass through it.
46
Some theories suggest it would need a strange type of energy that pushes the walls apart, but we do not know whether enough of this energy can exist.
47
But what if, instead of cutting a shortcut through space -time, we created a machine that twists the fabric of space and time itself?
48
That leads to the next method, the Tipler Cylinder.
49
A Tipler cylinder is a theoretical time machine made from a gigantic spinning tube.
50
To picture it, stand beside a chair and walk one full circle around it.
51
You return to the same spot but at a later point in time.
52
Now imagine the chair spinning so fast that it twists the floor around it into a whirlpool.
53
Each time you walk around, the twisted floor pulls your path backwards slightly.
54
A Tipler cylinder would do something similar to space and time.
55
The cylinder would need to be incredibly long, extremely heavy and spinning almost as fast as light.
56
As it turns, it would twist space -time around itself.
57
A spacecraft could circle the cylinder and follow this twisted path.
58
Normally, it would return to the same place later.
59
But if space -time were twisted enough, it could return before the journey began.
60
The next method uses something that may already exist.
61
These are cosmic strings.
62
Despite the name, these would not be physical strings.
63
Cosmic strings are incredibly thin lines of trapped energy, possibly left behind when the early universe formed.
64
Each string would change the shape of the space around it.
65
Imagine a long brick wall, remove one thin vertical slice, then pull the two remaining sides together and join them.
66
The wall still looks complete, but it now contains fewer bricks.
67
Traveling around it would therefore take slightly less distance than before.
68
A cosmic string would do something similar to space it would
69
remove a tiny wedge from its usual shape then join the remaining edges together
70
but the next method does not search for distorted space it
71
creates its own this is the warp drive method you sit inside your spacecraft
72
and activate the warp drive the engines do not push you
73
forwards instead space begins shrinking in front of the ship
74
and expanding behind it your spacecraft remains inside a calm bubble
75
while the universe moves around you like standing still on a conveyor belt
76
that carries the floor beneath your feet the real problem begins
77
when two carefully arranged warp bubbles move in different directions and reference frames.
78
Together, they could form a closed route through space -time.
79
You leave Earth, enter the first bubble, transfer into the second, and arrive home before the first engine was activated.
80
You might see technicians still preparing the ship you have already returned in, but a warp drive carries distorted space with the ship.
81
The next method leaves the shortcut behind, the Krasnikov tube.
82
A Krasnikov tube would create a permanent shortcut through space -time.
83
Unlike a warp bubble, the shortcut would not move with the spacecraft.
84
Instead, the first ship must travel normally towards a distant star, changing the space along the route behind it.
85
Think of digging a railway tunnel through a mountain.
86
The first journey is slow because the tunnel does not exist yet.
87
But once completed, every return journey can use the shorter route.
88
A Krasnikov tube would work in a similar way.
89
Inside the tunnel, space would be shaped so
90
that the spacecraft could return to Earth much faster than light could travel through normal space.
91
One tube only creates a rapid return route, but two tubes built along different paths could form a complete loop.
92
A spacecraft could travel through one tube, return through the other, and arrive on Earth before it originally departed.
93
The problem is that the tube would require strange negative energy spread along its walls, and we do not know how to create or control enough of it.
94
But the next method does not send a spacecraft into the past.
95
It sends a message.
96
This is a tachyon antitelephone.
97
This is a theoretical method of sending a message into the past using something that travels faster than light.
98
The signal could be carried by hypothetical particles called tachyons, which would always move faster than light.
99
Imagine sending a message to a spacecraft moving away from Earth.
100
Because the signal travels faster than light, the order of events can become twisted.
101
From the spacecraft's point of view, the message may arrive before Earth sent it.
102
The spacecraft could then send a faster -than -light reply back.
103
That reply could reach Earth before the original message was written.
104
Your phone could ring with a warning from the future, telling you not to send a message you have not typed yet.
105
But if you follow the warning and never send it, why was the warning sent back?
106
This is the main problem.
107
The anti -telephone could create a message that prevents its own existence.
108
Tachyons have never been discovered, and physics may forbid faster -than -light information entirely.
109
But the next method does not use a signal traveling through normal space.
110
It sends a particle into a loop where it can meet its own past.
111
This is the quantum time loop method.
112
Imagine rolling a ball into a tunnel.
113
A few seconds before the ball enters, an older copy rolls out of the other side.
114
Both versions now exist at the same time.
115
But what happens if the older ball blocks the younger one from entering the tunnel?
116
If the younger ball never enters, the older ball could never have appeared to block it.
117
The older particle may only interfere in a way that still allows its younger version to enter the loop.
118
Other models suggest several possible outcomes could exist at once, with only the self -consistent result surviving.
119
This means the particle could interact with its own past
120
but it could never create an impossible history
121
so far scientists have only simulated this behavior with quantum systems nothing has actually been sent backwards through time
122
but the next method would create a much larger loop by
123
bending space -time inside an enormous ring the ori time machine imagine a machine
124
that could create a loop through time inside an enormous donut
125
-shaped region of space at the center would be an empty
126
ring surrounded by matter arranged to bend space time in a
127
precise way as the space time inside the ring changes ordinary circular paths could eventually become paths into the past.
128
Think of driving around a roundabout.
129
Normally, each lap brings you back to the same place a few seconds later.
130
Inside the Ori time machine, spacetime would be bent so strongly that each lap could bring you back to the same place a few seconds earlier.
131
Keep circling, and you could travel farther into the past.
132
Unlike many time machine designs, the original model does not require negative energy matter around its empty core.
133
However, nobody knows whether the structure could be built or remain stable once the time loops begin forming.
134
But the final method needs no tunnel, cylinder, or ring.
135
It requires the entire universe to rotate.
136
The Godel Universe.
137
You launch your spacecraft and travel forwards through space.
138
There is no wormhole waiting ahead.
139
No cylinder spins beside you, and your ship never breaks the speed of light.
140
You simply continue traveling around the universe.
141
But this universe is rotating, not galaxies spinning inside space.
142
The structure of space -time itself has a global rotation built into it.
143
That rotation tilts the directions leading towards the future until a
144
sufficiently large path can curve all the way back towards the past.
145
Imagine walking forwards along the surface of Earth.
146
You never turn around, yet eventually the curve of the planet brings you back to where you started.
147
Now replace the surface of Earth with space -time.
148
You complete the journey and return not only to the same location, but to an earlier moment.
149
You could watch your own spacecraft, preparing to launch.
150
The disturbing part is that nothing locally appeared to go wrong.
151
You always moved forwards.
152
Every clock aboard the ship ticked normally.
153
The universe simply connected your future to your past.
154
Our universe does not appear to rotate in the way required by Godel's model, so this is not a route available to us.
155
But the equations show that general relativity can describe entire universes where time is not a straight road.
156
It is a landscape containing paths that lead back to places you have already lived.
157
If you guys had a time machine, where would you travel to?
158
Let me know in the comments below.
159
Don't forget to like, subscribe, and be sure to check out my other videos.
160
There's a whole playlist full of them in the description below.
アプリをダウンロード
流暢に話すために必要なすべて
AI発音採点文ごとに採点
IPA練習すべての音をマスター
単語学習自分の単語帳を作る
単語ゲーム遊びながら覚える
同じチャンネル
FOR YOU
おすすめ動画
C13
147 文
We Traveled Back in Time. Now Physicists Are Angry.
Daily ConversationUniversity StudentsWorking Adults
C16
16 文
How You Can Live Forever... Maybe.
IELTS PrepTOEFL PrepUniversity Students
C11
23 文
Black Hole Documentary 2019 - Part 1
Daily ConversationUniversity StudentsWorking Adults
C1110
6 文
Neuroscience of Time
Daily ConversationUniversity StudentsWorking Adults
B22
41 文
Why are airplanes slower than they used to be Alex Gendler
Daily ConversationUniversity StudentsWorking Adults
C1370 文
Are We Living Inside an Alien Control System?
Daily ConversationUniversity StudentsWorking Adults
C12
224 文
20% Speed of Light!! NEW Light Engine is INSANE!
Daily ConversationUniversity StudentsWorking Adults
C12
47 文
We Found Galaxies Too Old for the Universe
Daily ConversationUniversity StudentsWorking Adults
C110
7 文
How a slinky falls in slow motion #shorts
University StudentsWorking Adults
C12
89 文
Fire in ZERO-G!!
IELTS PrepTOEFL PrepUniversity Students
C13
169 文
It Sucks for 3 Days But It Makes Waking Up Early Effortless - Dr Andrew Huberman
Business EnglishUniversity StudentsWorking Adults
C121
25 文
Is Binge Watching Bad For You?
Daily ConversationUniversity StudentsWorking Adults
動画で英語学習の楽しさを発見しよう！
このビデオでは、時間旅行の仕組みについて科学的な説明がされています。難しい単語もありますが、リズム豊かな語り口が特徴で、英語スピーキング練習に最適です。日常会話だけでなく、学術的な表現も学べる貴重な素材です。
日常使いに役立つ5つのフレーズ
- "Imagine two identical twins."（2人の全く同じ双子を想像してみてください）- 説明を始める時に使えるフレーズ。
- "This happens because..."（これは～という理由で起こります）- 原因を説明する基本表現。
- "Think of it like..."（～のように考えてみてください）- 例えでわかりやすく説明する時に便利。
- "The problem is that..."（問題は～ということです）- 課題や難点を指摘するフレーズ。
- "To picture it..."（それをイメージするには～）- 視覚的な説明を促す時に使えます。
shadow speechで発音を磨くステップ
このビデオの速さやアクセントに慣れるために、shadow speak（シャドーイング）を使いましょう。以下のステップで練習してみてください。
ステップ1：ビデオを1回聴き、全体の流れを把握する
最初は字幕を見ながらもいいです。時間旅行の説明の構造（速さ・重力・凍結・ワームホール・チプラー円柱）を理解し、語彙の意味を確認しましょう。
ステップ2：1文ずつ繰り返し、リズムに合わせて発音する
ビデオを1文ずつ止め、すぐに後追いで発音します。"Speed time dilation."のような短いフレーズから始め、"The closer the spacecraft moves towards it, the deeper it travels into this warped region."のような長い文に挑戦しましょう。アクセントの位置やポーズを注意深く観察し、自分の口になじませます。
ステップ3：字幕を隠して、完全に追従する
慣れてきたら字幕を消し、ネイティブスピーカーの発音に合わせて即座に話します。これで英語の発音を良くするだけでなく、リスニング力も上がります。失敗しても大丈夫！何度も繰り返すことが大切です。
動画で英語学習するのは楽しいですね。この方法で英語スピーキング練習を続けると、自然に会話力が向上します。毎日10分でも続けてみてください！
この動画の文法
話し手がよく使っている文型を、動画の実際の表現とともに紹介します。
| 文型 | 動画での表現 |
|---|---|
| 受動態 be + 過去分詞 — 誰がするかより、何が起きるかに焦点を当てる | be lowered · are easily damaged · were twisted |
| 現在完了形 have/has + 過去分詞 — 過去の出来事が今も関係している | have already returned · have not typed · have never been discovered |
シャドーイングとは？英語上達に効果的な理由
シャドーイング（Shadowing）は、もともとプロの通訳者養成プログラムで開発された言語学習法で、多言語習得者として知られるDr. Alexander Arguelles によって広く普及されました。方法はシンプルですが非常に効果的：ネイティブスピーカーの英語を聞きながら、1〜2秒の遅延で声に出してすぐに繰り返す——まるで「影（shadow）」のように話者を追いかけます。文法ドリルや受動的なリスニングと異なり、シャドーイングは脳と口の筋肉が同時にリアルタイムで英語を処理・再現することを強制します。研究により、発音精度、抑揚、リズム、連音、リスニング力、そして会話の流暢さが大幅に向上することが確認されています。IELTSスピーキング対策や自然な英語コミュニケーションを目指す方に特におすすめです。